Timeline Of Indian Innovation
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Timeline of Indian innovation encompasses key events in the
history of technology The history of technology is the history of the invention of tools and techniques and is one of the categories of world history. Technology can refer to methods ranging from as simple as stone tools to the complex genetic engineering and info ...
in the subcontinent historically referred to as India and the modern Indian state. The entries in this timeline fall into the following categories:
architecture Architecture is the art and technique of designing and building, as distinguished from the skills associated with construction. It is both the process and the product of sketching, conceiving, planning, designing, and constructing building ...
,
astronomy Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...
,
cartography Cartography (; from grc, χάρτης , "papyrus, sheet of paper, map"; and , "write") is the study and practice of making and using maps. Combining science, aesthetics and technique, cartography builds on the premise that reality (or an im ...
,
metallurgy Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys. Metallurgy encompasses both the sc ...
,
logic Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the science of deductively valid inferences or of logical truths. It is a formal science investigating how conclusions follow from premises ...
,
mathematics Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...
,
metrology Metrology is the scientific study of measurement. It establishes a common understanding of units, crucial in linking human activities. Modern metrology has its roots in the French Revolution's political motivation to standardise units in Fran ...
,
mineralogy Mineralogy is a subject of geology specializing in the scientific study of the chemistry, crystal structure, and physical (including optical) properties of minerals and mineralized artifacts. Specific studies within mineralogy include the proces ...
,
automobile engineering Automotive engineering, along with aerospace engineering and naval architecture, is a branch of vehicle engineering, incorporating elements of mechanical, electrical, electronic, software, and safety engineering as applied to the design, manufactu ...
,
information technology Information technology (IT) is the use of computers to create, process, store, retrieve, and exchange all kinds of data . and information. IT forms part of information and communications technology (ICT). An information technology system (I ...
,
communications Communication (from la, communicare, meaning "to share" or "to be in relation with") is usually defined as the transmission of information. The term may also refer to the message communicated through such transmissions or the field of inquir ...
,
space Space is the boundless three-dimensional extent in which objects and events have relative position and direction. In classical physics, physical space is often conceived in three linear dimensions, although modern physicists usually consider ...
and
polar Polar may refer to: Geography Polar may refer to: * Geographical pole, either of two fixed points on the surface of a rotating body or planet, at 90 degrees from the equator, based on the axis around which a body rotates * Polar climate, the c ...
technology. This timeline examines scientific and medical discoveries, products and technologies introduced by various peoples of India.
Invention An invention is a unique or novel device, method, composition, idea or process. An invention may be an improvement upon a machine, product, or process for increasing efficiency or lowering cost. It may also be an entirely new concept. If an i ...
s are regarded as technological firsts developed in India, and as such does not include foreign technologies which India acquired through contact.


7000 BCE

* Ancient dentistry: The
Indus Valley civilization The Indus Valley Civilisation (IVC), also known as the Indus Civilisation was a Bronze Age civilisation in the northwestern regions of South Asia, lasting from 3300 BCE to 1300 BCE, and in its mature form 2600 BCE to 1900&n ...
(IVC) has yielded evidence of dentistry being practised as far back as 7000 BC. An IVC site in
Mehrgarh Mehrgarh (; ur, ) is a Neolithic archaeological site (dated ) situated on the Kacchi Plain of Balochistan in Pakistan. It is located near the Bolan Pass, to the west of the Indus River and between the modern-day Pakistani cities of Quetta, Ka ...
indicates that this form of dentistry involved curing tooth related disorders with
bow drill A bow drill is a simple hand-operated type of tool, consisting of a rod (the ''spindle'' or ''drill shaft'') that is set in rapid rotary motion by means of a cord wrapped around it, kept taut by a bow which is pushed back and forth with one han ...
s operated, perhaps, by skilled bead crafters.


5000 BCE

*
Ayurveda Ayurveda () is an alternative medicine system with historical roots in the Indian subcontinent. The theory and practice of Ayurveda is pseudoscientific. Ayurveda is heavily practiced in India and Nepal, where around 80% of the population repo ...
: Ayurveda is a system of medicine with historical roots in the Indian subcontinent. The origins of Ayurveda have been traced back to around 5,000
BCE Common Era (CE) and Before the Common Era (BCE) are year notations for the Gregorian calendar (and its predecessor, the Julian calendar), the world's most widely used calendar era. Common Era and Before the Common Era are alternatives to the or ...
, when they originated as an oral tradition.


3100 BCE

*
Yoga Yoga (; sa, योग, lit=yoke' or 'union ) is a group of physical, mental, and spiritual practices or disciplines which originated in ancient India and aim to control (yoke) and still the mind, recognizing a detached witness-consciou ...
: The origins of yoga are a matter of debate. There is no consensus on its chronology or specific origin other than that yoga developed in ancient India. Suggested origins are the
Indus Valley civilization The Indus Valley Civilisation (IVC), also known as the Indus Civilisation was a Bronze Age civilisation in the northwestern regions of South Asia, lasting from 3300 BCE to 1300 BCE, and in its mature form 2600 BCE to 1900&n ...
(3300–1900 BCE) and pre-Vedic Eastern states of India, the
Vedic period The Vedic period, or the Vedic age (), is the period in the late Bronze Age and early Iron Age of the history of India when the Vedic literature, including the Vedas (ca. 1300–900 BCE), was composed in the northern Indian subcontinent, betw ...
(1500–500 BCE), and the
śramaṇa ''Śramaṇa'' (Sanskrit; Pali: ''𑀲𑀫𑀦'') means "one who labours, toils, or exerts themselves (for some higher or religious purpose)" or "seeker, one who performs acts of austerity, ascetic".Monier Monier-Williams, श्रमण śr ...
movement.


2500 BCE

* Ancient
flush toilet A flush toilet (also known as a flushing toilet, water closet (WC) – see also toilet names) is a toilet that disposes of human waste (principally urine and feces) by using the force of water to ''flush'' it through a drainpipe to another lo ...
systems: Toilets that used water were used in the
Indus Valley civilization The Indus Valley Civilisation (IVC), also known as the Indus Civilisation was a Bronze Age civilisation in the northwestern regions of South Asia, lasting from 3300 BCE to 1300 BCE, and in its mature form 2600 BCE to 1900&n ...
. The cities of
Harappa Harappa (; Urdu/ pnb, ) is an archaeological site in Punjab, Pakistan, about west of Sahiwal. The Bronze Age Harappan civilisation, now more often called the Indus Valley Civilisation, is named after the site, which takes its name from a mode ...
and
Mohenjo-daro Mohenjo-daro (; sd, موئن جو دڙو'', ''meaning 'Mound of the Dead Men';sewage system Sewerage (or sewage system) is the infrastructure that conveys sewage or surface runoff (stormwater, meltwater, rainwater) using sewers. It encompasses components such as receiving drains, manholes, pumping stations, storm overflows, and screeni ...
. See also ''
Sanitation of the Indus Valley Civilisation The ancient Indus Valley Civilization in South Asia, including current day's Pakistan and north India, was prominent in infrastructure, hydraulic engineering, and had many water supply and sanitation devices that are the first known examples o ...
''. *
Diamond Diamond is a Allotropes of carbon, solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Another solid form of carbon known as graphite is the Chemical stability, chemically stable form of car ...
mining: Diamonds are thought to have been first recognized and mined in
India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
, where significant
alluvial deposit Alluvium (from Latin ''alluvius'', from ''alluere'' 'to wash against') is loose clay, silt, sand, or gravel that has been deposited by running water in a stream bed, on a floodplain, in an alluvial fan or beach, or in similar settings. Alluv ...
s of the stone could be found many centuries ago along the rivers Penner,
Krishna Krishna (; sa, कृष्ण ) is a major deity in Hinduism. He is worshipped as the eighth avatar of Vishnu and also as the Supreme god in his own right. He is the god of protection, compassion, tenderness, and love; and is one ...
and
Godavari The Godavari ( IAST: ''Godāvarī'' od̪aːʋəɾiː is India's second longest river after the Ganga river and drains into the third largest basin in India, covering about 10% of India's total geographical area. Its source is in Trimbakesh ...
. Diamonds have been known in India for at least 3,000 years but most likely 6,000 years. *
Stepwell Stepwells (also known as vavs or baori) are wells or ponds with a long corridor of steps that descend to the water level. Stepwells played a significant role in defining subterranean architecture in western India from 7th to 19th century. So ...
: Earliest clear evidence of the origins of the stepwell is found in the Indus Valley Civilization's archaeological site at
Mohenjodaro Mohenjo-daro (; sd, موئن جو دڙو'', ''meaning 'Mound of the Dead Men';Bhinmal Bhinmal (previously Shrimal Nagar) is an ancient town in the Jalore District of Rajasthan, India. It is south of Jalore. Bhinmal was the capital of the Bhil king, then the capital of Gurjaradesa, comprising modern-day southern Rajasthan and nor ...
(850-950 CE) were constructed.


2400 BCE

*
Ruler A ruler, sometimes called a rule, line gauge, or scale, is a device used in geometry and technical drawing, as well as the engineering and construction industries, to measure distances or draw straight lines. Variants Rulers have long ...
: Rulers made from Ivory were in use by the Indus Valley Civilization in what today is Pakistan and some parts of Western India prior to 1500 BCE. Excavations at Lothal (2400 BCE) have yielded one such ruler calibrated to about 1/16 of an inch—less than 2
millimeters 330px, Different lengths as in respect to the electromagnetic spectrum, measured by the metre and its derived scales. The microwave is between 1 meter to 1 millimeter. The millimetre (American and British English spelling differences#-re, -er, ...
. Ian Whitelaw (2007) holds that 'The Mohenjo-Daro ruler is divided into units corresponding to 1.32 inches (33.5 mm) and these are marked out in decimal subdivisions with amazing accuracy—to within 0.005 of an inch. They correspond closely with the "hasta" increments of 1 3/8 inches traditionally used in South India in ancient architecture. Ancient bricks found throughout the region have dimensions that correspond to these units.' Shigeo Iwata (2008) further writes 'The minimum division of graduation found in the segment of an ivory-made linear measure excavated in Lothal was 1.79 mm (that corresponds to 1/940 of a fathom), while that of the fragment of a shell-made one from Mohenjo-daro was 6.72 mm (1/250 of a fathom), and that of bronze-made one from Harapa was 9.33 mm (1/180 of a fathom).' The weights and measures of the Indus civilization also reached Persia and
Central Asia Central Asia, also known as Middle Asia, is a subregion, region of Asia that stretches from the Caspian Sea in the west to western China and Mongolia in the east, and from Afghanistan and Iran in the south to Russia in the north. It includes t ...
, where they were further modified. *
Weighing scale A scale or balance is a device used to measure weight or mass. These are also known as mass scales, weight scales, mass balances, and weight balances. The traditional scale consists of two plates or bowls suspended at equal distances from a ...
: The earliest evidence for the existence of weighing scale dates to 2400 BC-1800 BC in the Indus valley civilization prior to which no banking was performed due to lack of scales.


2000 BCE

*
Plastic surgery Plastic surgery is a surgical specialty involving the restoration, reconstruction or alteration of the human body. It can be divided into two main categories: reconstructive surgery and cosmetic surgery. Reconstructive surgery includes craniofa ...
: Plastic surgery was being carried out in India by 2000 BCE. The system of punishment by deforming a miscreant's body may have led to an increase in demand for this practice. The surgeon
Sushruta Sushruta, or ''Suśruta'' (Sanskrit: सुश्रुत, IAST: , ) was an ancient Indian physician. The ''Sushruta Samhita'' (''Sushruta's Compendium''), a treatise ascribed to him, is one of the most important surviving ancient treatises on ...
contributed mainly to the field of plastic and cataract surgery. The medical works of both Sushruta and
Charak Charak may refer to: *Bandar Charak, a city in Iran * Charak, Bushehr, a village in Iran *Charaka, ancient Ayurveda figure *Charak Puja Charak Puja or Charak Mela (also known as ''Cadak'', ''Chadak'', ''Nil Puja'' and ''Hajrha Puja'') is a Hind ...
were translated into Arabic language during the
Abbasid Caliphate The Abbasid Caliphate ( or ; ar, الْخِلَافَةُ الْعَبَّاسِيَّة, ') was the third caliphate to succeed the Islamic prophet Muhammad. It was founded by a dynasty descended from Muhammad's uncle, Abbas ibn Abdul-Muttalib ...
(750 CE). These translated Arabic works made their way into Europe via intermediaries. In
Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical re ...
, the Branca family of
Sicily (man) it, Siciliana (woman) , population_note = , population_blank1_title = , population_blank1 = , demographics_type1 = Ethnicity , demographics1_footnotes = , demographi ...
and Gaspare Tagliacozzi of Bologna became familiar with the techniques of Sushruta.


700 BCE

*
Pythagorean theorem In mathematics, the Pythagorean theorem or Pythagoras' theorem is a fundamental relation in Euclidean geometry between the three sides of a right triangle. It states that the area of the square whose side is the hypotenuse (the side opposite t ...
:
Mesopotamia Mesopotamia ''Mesopotamíā''; ar, بِلَاد ٱلرَّافِدَيْن or ; syc, ܐܪܡ ܢܗܪ̈ܝܢ, or , ) is a historical region of Western Asia situated within the Tigris–Euphrates river system, in the northern part of the F ...
n,
Indian Indian or Indians may refer to: Peoples South Asia * Indian people, people of Indian nationality, or people who have an Indian ancestor ** Non-resident Indian, a citizen of India who has temporarily emigrated to another country * South Asia ...
and
Chinese mathematicians Mathematics in China emerged independently by the 11th century BCE. The Chinese independently developed a real number system that includes significantly large and negative numbers, more than one numeral system ( base 2 and base 10), algebra, geomet ...
all discovered the theorem independently and, in some cases, provided proofs for special cases. In
India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
, the ''
Baudhayana The (Sanskrit: बौधायन) are a group of Vedic Sanskrit texts which cover dharma, daily ritual, mathematics and is one of the oldest Dharma-related texts of Hinduism that have survived into the modern age from the 1st-millennium BCE. Th ...
Sulba Sutra'', the dates of which are given variously as between the 8th and 5th century BC, contains a list of
Pythagorean triples A Pythagorean triple consists of three positive integers , , and , such that . Such a triple is commonly written , and a well-known example is . If is a Pythagorean triple, then so is for any positive integer . A primitive Pythagorean triple is ...
discovered algebraically, a statement of the Pythagorean theorem, and a
geometrical Geometry (; ) is, with arithmetic, one of the oldest branches of mathematics. It is concerned with properties of space such as the distance, shape, size, and relative position of figures. A mathematician who works in the field of geometry is ca ...
proof of the Pythagorean theorem for an
isosceles In geometry, an isosceles triangle () is a triangle that has two sides of equal length. Sometimes it is specified as having ''exactly'' two sides of equal length, and sometimes as having ''at least'' two sides of equal length, the latter versio ...
right triangle. The ''
Apastamba ''Āpastamba Dharmasūtra'' (Sanskrit: आपस्तम्ब धर्मसूत्र) is a Sanskrit text and one of the oldest Dharma-related texts of Hinduism that have survived into the modern age from the 1st-millennium BCE. It is one of ...
Sulba Sutra'' (c. 600 BC) contains a numerical proof of the general Pythagorean theorem, using an area computation. Van der Waerden believed that "it was certainly based on earlier traditions". Carl Boyer states that the Pythagorean theorem in '' Śulba-sũtram'' may have been influenced by ancient Mesopotamian math, but there is no conclusive evidence in favor or opposition of this possibility.


500 BCE

*
Formal grammar In formal language theory, a grammar (when the context is not given, often called a formal grammar for clarity) describes how to form strings from a language's alphabet that are valid according to the language's syntax. A grammar does not describe ...
: Panini in his treatise Astadyayi gives formal production rules and definitions to describe the formal grammar of
Sanskrit Sanskrit (; attributively , ; nominally , , ) is a classical language belonging to the Indo-Aryan branch of the Indo-European languages. It arose in South Asia after its predecessor languages had diffused there from the northwest in the late ...
. In
formal language theory In logic, mathematics, computer science, and linguistics, a formal language consists of words whose letters are taken from an alphabet and are well-formed according to a specific set of rules. The alphabet of a formal language consists of symb ...
, a grammar (when the context is not given, often called a formal grammar for clarity) is a set of production rules for
strings String or strings may refer to: *String (structure), a long flexible structure made from threads twisted together, which is used to tie, bind, or hang other objects Arts, entertainment, and media Films * ''Strings'' (1991 film), a Canadian anim ...
in a
formal language In logic, mathematics, computer science, and linguistics, a formal language consists of words whose letters are taken from an alphabet and are well-formed according to a specific set of rules. The alphabet of a formal language consists of symb ...
. The rules describe how to form strings from the language's
alphabet An alphabet is a standardized set of basic written graphemes (called letters) that represent the phonemes of certain spoken languages. Not all writing systems represent language in this way; in a syllabary, each character represents a syll ...
that are valid according to the language's
syntax In linguistics, syntax () is the study of how words and morphemes combine to form larger units such as phrases and sentences. Central concerns of syntax include word order, grammatical relations, hierarchical sentence structure ( constituency) ...
. A grammar does not describe the meaning of the stringsor what can be done with them in whatever context—only their form.


300 BCE

*
Atomism Atomism (from Greek , ''atomon'', i.e. "uncuttable, indivisible") is a natural philosophy proposing that the physical universe is composed of fundamental indivisible components known as atoms. References to the concept of atomism and its atoms ...
: References to the concept of atomism and its atoms are found in
ancient India According to consensus in modern genetics, anatomically modern humans first arrived on the Indian subcontinent from Africa between 73,000 and 55,000 years ago. Quote: "Y-Chromosome and Mt-DNA data support the colonization of South Asia by m ...
and
ancient Greece Ancient Greece ( el, Ἑλλάς, Hellás) was a northeastern Mediterranean civilization, existing from the Greek Dark Ages of the 12th–9th centuries BC to the end of classical antiquity ( AD 600), that comprised a loose collection of cult ...
. In the West, atomism emerged in the 5th century BCE with
Leucippus Leucippus (; el, Λεύκιππος, ''Leúkippos''; fl. 5th century BCE) is a pre-Socratic Greek philosopher who has been credited as the first philosopher to develop a theory of atomism. Leucippus' reputation, even in antiquity, was obscured ...
and
Democritus Democritus (; el, Δημόκριτος, ''Dēmókritos'', meaning "chosen of the people"; – ) was an Ancient Greek pre-Socratic philosopher from Abdera, primarily remembered today for his formulation of an atomic theory of the universe. No ...
. In
India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
, the
Jain Jainism ( ), also known as Jain Dharma, is an Indian religion. Jainism traces its spiritual ideas and history through the succession of twenty-four tirthankaras (supreme preachers of ''Dharma''), with the first in the current time cycle being ...
, Ajivika and
Carvaka Charvaka ( sa, चार्वाक; IAST: ''Cārvāka''), also known as ''Lokāyata'', is an ancient school of Indian materialism. Charvaka holds direct perception, empiricism, and conditional inference as proper sources of knowledge, embrace ...
schools of atomism date back to the 4th century BCE. The
Nyaya (Sanskrit: न्याय, ''nyā-yá''), literally meaning "justice", "rules", "method" or "judgment",Vaisheshika Vaisheshika or Vaiśeṣika ( sa, वैशेषिक) is one of the six schools of Indian philosophy (Vedic systems) from ancient India. In its early stages, the Vaiśeṣika was an independent philosophy with its own metaphysics, epistemolog ...
schools later developed theories on how atoms combined into more complex objects. Whether Indian culture influenced Greek or vice versa or whether both evolved independently is a matter of dispute.


200 BCE

*
Crucible steel Crucible steel is steel made by melting pig iron (cast iron), iron, and sometimes steel, often along with sand, glass, ashes, and other flux (metallurgy), fluxes, in a crucible. In ancient times steel and iron were impossible to melt using char ...
: Perhaps as early as 300 BC—although certainly by 200 BC—high quality steel was being produced in southern India, by what Europeans would later call the crucible technique. In this system, high-purity wrought iron, charcoal, and glass were mixed in a crucible and heated until the iron melted and absorbed the carbon.


100

* Hindu number system: With
decimal The decimal numeral system (also called the base-ten positional numeral system and denary or decanary) is the standard system for denoting integer and non-integer numbers. It is the extension to non-integer numbers of the Hindu–Arabic numeral ...
place-value and a symbol for zero, this system was the ancestor of the widely used
Arabic numeral Arabic numerals are the ten numerical digits: , , , , , , , , and . They are the most commonly used symbols to write Decimal, decimal numbers. They are also used for writing numbers in other systems such as octal, and for writing identifiers ...
system. It was developed in the Indian subcontinent between the 1st and 6th centuries CE.


200

*
Cataract surgery Cataract surgery, also called lens replacement surgery, is the removal of the natural lens of the eye (also called "crystalline lens") that has developed an opacification, which is referred to as a cataract, and its replacement with an intraocu ...
: Cataract surgery was known to the Indian physician Sushruta (3rd century CE). In India, cataract surgery was performed with a special tool called the ''Jabamukhi Salaka'', a curved needle used to loosen the lens and push the cataract out of the field of vision. The eye would later be soaked with warm butter and then bandaged. Though this method was successful, Susruta cautioned that cataract surgery should only:. Greek philosophers and scientists traveled to India where these surgeries were performed by physicians. The removal of cataract by surgery was also introduced into China from India. *
Sugar Sugar is the generic name for sweet-tasting, soluble carbohydrates, many of which are used in food. Simple sugars, also called monosaccharides, include glucose, fructose, and galactose. Compound sugars, also called disaccharides or double ...
: First ever sugar granules appear in gupta empire from where the technology spread


500

*
Zero 0 (zero) is a number representing an empty quantity. In place-value notation Positional notation (or place-value notation, or positional numeral system) usually denotes the extension to any base of the Hindu–Arabic numeral system (or ...
, symbol: Indians were the first to use the zero as a symbol and in arithmetic operations, although Babylonians used zero to signify the 'absent'. In those earlier times a blank space was used to denote zero, later when it created confusion a dot was used to denote zero (could be found in Bakhshali manuscript). In 500 AD circa
Aryabhata Aryabhata (ISO: ) or Aryabhata I (476–550 CE) was an Indian mathematician and astronomer of the classical age of Indian mathematics and Indian astronomy. He flourished in the Gupta Era and produced works such as the ''Aryabhatiya'' (which ...
again gave a new symbol for zero (''0'').


600

*
Brahmagupta–Fibonacci identity In algebra, the Brahmagupta–Fibonacci identity expresses the product of two sums of two squares as a sum of two squares in two different ways. Hence the set of all sums of two squares is closed under multiplication. Specifically, the identity say ...
,
Brahmagupta formula In Euclidean geometry, Brahmagupta's formula is used to find the area of any cyclic quadrilateral (one that can be inscribed in a circle) given the lengths of the sides; its generalized version (Bretschneider's formula) can be used with non-cyclic ...
,
Brahmagupta matrix In mathematics, the following matrix was given by Indian mathematician Brahmagupta: :B(x,y) = \begin x & y \\ \pm ty & \pm x \end. It satisfies :B(x_1,y_1) B(x_2,y_2) = B(x_1 x_2 \pm ty_1 y_2,x_1 y_2 \pm y_1 x_2).\, Powers of the matrix are def ...
, and
Brahmagupta theorem In geometry, Brahmagupta's theorem states that if a cyclic quadrilateral is orthodiagonal (that is, has perpendicular diagonals), then the perpendicular to a side from the point of intersection of the diagonals always bisects the opposite side. I ...
: Discovered by the Indian mathematician, Brahmagupta (598–668 CE). * Algebraic abbreviations: The mathematician
Brahmagupta Brahmagupta ( – ) was an Indian mathematician and astronomer. He is the author of two early works on mathematics and astronomy: the ''Brāhmasphuṭasiddhānta'' (BSS, "correctly established doctrine of Brahma", dated 628), a theoretical trea ...
had begun using abbreviations for unknowns by the 7th century. He employed abbreviations for multiple unknowns occurring in one complex problem. Brahmagupta also used abbreviations for
square roots In mathematics, a square root of a number is a number such that ; in other words, a number whose ''square'' (the result of multiplying the number by itself, or  ⋅ ) is . For example, 4 and −4 are square roots of 16, because . E ...
and cube roots. *
Chaturanga Chaturanga ( sa, चतुरङ्ग; ') is an ancient Indian strategy game. While there is some uncertainty, the prevailing view among chess historians is that it is the common ancestor of the board games chess (European), xiangqi (Chinese), ...
: The precursor of
chess Chess is a board game for two players, called White and Black, each controlling an army of chess pieces in their color, with the objective to checkmate the opponent's king. It is sometimes called international chess or Western chess to disti ...
originated in India during the
Gupta dynasty The Gupta Empire was an Outline of ancient India, ancient Indian empire which existed from the early 4th century CE to late 6th century CE. At its zenith, from approximately 319 to 467 CE, it covered much of the Indian subcontinent. This period ...
(c. 280-550 CE). Both the
Persians The Persians are an Iranian ethnic group who comprise over half of the population of Iran. They share a common cultural system and are native speakers of the Persian language as well as of the languages that are closely related to Persian. ...
and
Arab The Arabs (singular: Arab; singular ar, عَرَبِيٌّ, DIN 31635: , , plural ar, عَرَب, DIN 31635: , Arabic pronunciation: ), also known as the Arab people, are an ethnic group mainly inhabiting the Arab world in Western Asia, ...
s ascribe the origins of the game of Chess to the Indians. The words for ''chess'' in
Old Persian Old Persian is one of the two directly attested Old Iranian languages (the other being Avestan language, Avestan) and is the ancestor of Middle Persian (the language of Sasanian Empire). Like other Old Iranian languages, it was known to its native ...
and
Arabic Arabic (, ' ; , ' or ) is a Semitic languages, Semitic language spoken primarily across the Arab world.Semitic languages: an international handbook / edited by Stefan Weninger; in collaboration with Geoffrey Khan, Michael P. Streck, Janet C ...
are and ''
shatranj Shatranj ( ar, شطرنج; fa, شترنج; from Middle Persian ''chatrang'' ) is an old form of chess, as played in the Sasanian Empire. Its origins are in the Indian game of chaturaṅga. Modern chess gradually developed from this game, as i ...
'' respectively — terms derived from '' caturaṅga'' in
Sanskrit Sanskrit (; attributively , ; nominally , , ) is a classical language belonging to the Indo-Aryan branch of the Indo-European languages. It arose in South Asia after its predecessor languages had diffused there from the northwest in the late ...
, which literally means 'an army of four divisions' or 'four corps'. Chess spread throughout the world and many variants of the game soon began taking shape. This game was introduced to the
Near East The ''Near East''; he, המזרח הקרוב; arc, ܕܢܚܐ ܩܪܒ; fa, خاور نزدیک, Xāvar-e nazdik; tr, Yakın Doğu is a geographical term which roughly encompasses a transcontinental region in Western Asia, that was once the hist ...
from India and became a part of the princely or courtly education of
Persian Persian may refer to: * People and things from Iran, historically called ''Persia'' in the English language ** Persians, the majority ethnic group in Iran, not to be conflated with the Iranic peoples ** Persian language, an Iranian language of the ...
nobility.
Buddhist Buddhism ( , ), also known as Buddha Dharma and Dharmavinaya (), is an Indian religion or philosophical tradition based on teachings attributed to the Buddha. It originated in northern India as a -movement in the 5th century BCE, and ...
pilgrims,
Silk Road The Silk Road () was a network of Eurasian trade routes active from the second century BCE until the mid-15th century. Spanning over 6,400 kilometers (4,000 miles), it played a central role in facilitating economic, cultural, political, and reli ...
traders and others carried it to the
Far East The ''Far East'' was a European term to refer to the geographical regions that includes East and Southeast Asia as well as the Russian Far East to a lesser extent. South Asia is sometimes also included for economic and cultural reasons. The ter ...
where it was transformed and assimilated into a game often played on the intersection of the lines of the board rather than within the squares. Chaturanga reached Europe through Persia, the
Byzantine empire The Byzantine Empire, also referred to as the Eastern Roman Empire or Byzantium, was the continuation of the Roman Empire primarily in its eastern provinces during Late Antiquity and the Middle Ages, when its capital city was Constantinopl ...
and the expanding
Arabian The Arabian Peninsula, (; ar, شِبْهُ الْجَزِيرَةِ الْعَرَبِيَّة, , "Arabian Peninsula" or , , "Island of the Arabs") or Arabia, is a peninsula of Western Asia, situated northeast of Africa on the Arabian Plate. ...
empire.
Muslims Muslims ( ar, المسلمون, , ) are people who adhere to Islam, a monotheistic religion belonging to the Abrahamic tradition. They consider the Quran, the foundational religious text of Islam, to be the verbatim word of the God of Abraha ...
carried Shatranj to
North Africa North Africa, or Northern Africa is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region, and it is sometimes defined as stretching from the Atlantic shores of Mauritania in ...
,
Sicily (man) it, Siciliana (woman) , population_note = , population_blank1_title = , population_blank1 = , demographics_type1 = Ethnicity , demographics1_footnotes = , demographi ...
, and Spain by the 10th century where it took its final modern form of chess. *
Ludo Ludo (; ) is a strategy board game for two to four players, in which the players race their four from start to finish according to the rolls of a single die. Like other cross and circle games, Ludo is derived from the Indian game Pachisi. The ...
:
Pachisi Pachisi (, Hindustani: əˈtʃiːsiː is a cross and circle board game that originated in Ancient India. It is described in the ancient text ''Mahabharata'' under the name of "Pasha". It is played on a board shaped like a symmetrical cross. A ...
originated in India by the 6th century. The earliest evidence of this game in India is the depiction of boards on the caves of Ajanta. This game was played by the
Mughal emperors The Mughal emperors ( fa, , Pādishāhān) were the supreme heads of state of the Mughal Empire on the Indian subcontinent, mainly corresponding to the modern countries of India, Pakistan, Afghanistan and Bangladesh. The Mughal rulers styled t ...
of India; a notable example being that of Akbar, who played ''living Pachisi'' using girls from his
harem Harem (Persian: حرمسرا ''haramsarā'', ar, حَرِيمٌ ''ḥarīm'', "a sacred inviolable place; harem; female members of the family") refers to domestic spaces that are reserved for the women of the house in a Muslim family. A hare ...
. A variant of this game, called Luodo, made its way to England during the British Raj. *
Spinning wheel A spinning wheel is a device for spinning thread or yarn from fibres. It was fundamental to the cotton textile industry prior to the Industrial Revolution. It laid the foundations for later machinery such as the spinning jenny and spinning f ...
: Invented in India between 500 and 1000 A.D. * Finite Difference
Interpolation In the mathematical field of numerical analysis, interpolation is a type of estimation, a method of constructing (finding) new data points based on the range of a discrete set of known data points. In engineering and science, one often has a n ...
: The Indian mathematician
Brahmagupta Brahmagupta ( – ) was an Indian mathematician and astronomer. He is the author of two early works on mathematics and astronomy: the ''Brāhmasphuṭasiddhānta'' (BSS, "correctly established doctrine of Brahma", dated 628), a theoretical trea ...
presented what is possibly the first instance of finite difference interpolation around 665 CE. *
Pascal's triangle In mathematics, Pascal's triangle is a triangular array of the binomial coefficients that arises in probability theory, combinatorics, and algebra. In much of the Western world, it is named after the French mathematician Blaise Pascal, although ot ...
: Described in the 6th century CE by Varahamihira and in the 10th century by
Halayudha Halayudha (Sanskrit: हलायुध) was a 10th-century Indian mathematician who wrote the ',Maurice Winternitz, ''History of Indian Literature'', Vol. III a commentary on Pingala's ''Chandaḥśāstra''. The latter contains a clear descrip ...
, commenting on an obscure reference by
Pingala Acharya Pingala ('; c. 3rd2nd century BCE) was an ancient Indian poet and mathematician, and the author of the ' (also called the ''Pingala-sutras''), the earliest known treatise on Sanskrit prosody. The ' is a work of eight chapters in the late ...
(the author of an earlier work on prosody) to the "Meru-prastaara", or the "Staircase of Mount Meru", in relation to binomial coefficients. (It was also independently discovered in the 10th or 11th century in Persia and China.)


700

*
Fibonacci numbers In mathematics, the Fibonacci numbers, commonly denoted , form a sequence, the Fibonacci sequence, in which each number is the sum of the two preceding ones. The sequence commonly starts from 0 and 1, although some authors start the sequence from ...
: This sequence was first described by
Virahanka Virahanka (Devanagari: विरहाङ्क) was an Indian prosodist who is also known for his work on mathematics. He may have lived in the 6th century, but it is also possible that he worked as late as the 8th century. His work on prosody ...
(c. 700 AD), Gopāla (c. 1135), and
Hemachandra Hemachandra was a 12th century () Indian Jain saint, scholar, poet, mathematician, philosopher, yogi, grammarian, law theorist, historian, lexicographer, rhetorician, logician, and prosodist. Noted as a prodigy by his contemporaries, he gain ...
(c. 1150), as an outgrowth of the earlier writings on Sanskrit prosody by
Pingala Acharya Pingala ('; c. 3rd2nd century BCE) was an ancient Indian poet and mathematician, and the author of the ' (also called the ''Pingala-sutras''), the earliest known treatise on Sanskrit prosody. The ' is a work of eight chapters in the late ...
(c. 200 BC). *
Earth's orbit Earth orbits the Sun at an average distance of 149.60 million km (92.96 million mi) in a counterclockwise direction as viewed from above the Northern Hemisphere. One complete orbit takes  days (1 sidereal year), during which time Earth ...
(
Sidereal year A sidereal year (, ; ), also called a sidereal orbital period, is the time that Earth or another planetary body takes to orbit the Sun once with respect to the fixed stars. Hence, for Earth, it is also the time taken for the Sun to return to the ...
): The
Hindu Hindus (; ) are people who religiously adhere to Hinduism.Jeffery D. Long (2007), A Vision for Hinduism, IB Tauris, , pages 35–37 Historically, the term has also been used as a geographical, cultural, and later religious identifier for ...
cosmological time cycles explained in the ''
Surya Siddhanta The ''Surya Siddhanta'' (; ) is a Sanskrit treatise in Indian astronomy dated to 505 CE,Menso Folkerts, Craig G. Fraser, Jeremy John Gray, John L. Berggren, Wilbur R. Knorr (2017)Mathematics Encyclopaedia Britannica, Quote: "(...) its Hindu inven ...
''(700 BCE-600 CE), give the average length of the sidereal year (the length of the Earth's revolution around the Sun) as 365.2563627 days, which is only a negligible 1.4 seconds longer than the modern value of 365.256363004 days. This remains the most accurate estimate for the length of the sidereal year anywhere in the world for over a thousand years.


1000

*
Chakravala method The ''chakravala'' method ( sa, चक्रवाल विधि) is a cyclic algorithm to solve indeterminate quadratic equations, including Pell's equation. It is commonly attributed to Bhāskara II, (c. 1114 – 1185 CE)Hoiberg & Ramchandani ...
: The Chakravala method, a cyclic algorithm to solve indeterminate
quadratic equation In algebra, a quadratic equation () is any equation that can be rearranged in standard form as ax^2 + bx + c = 0\,, where represents an unknown (mathematics), unknown value, and , , and represent known numbers, where . (If and then the equati ...
s is commonly attributed to
Bhāskara II Bhāskara II (c. 1114–1185), also known as Bhāskarāchārya ("Bhāskara, the teacher"), and as Bhāskara II to avoid confusion with Bhāskara I, was an Indian mathematician and astronomer. From verses, in his main work, Siddhānta Shiroman ...
, (c. 1114 – 1185 CE) although some attribute it to
Jayadeva Jayadeva (; born ), also spelt Jaideva, was a Sanskrit poet during the 12th century. He is most known for his epic poem ''Gita Govinda'' which concentrates on Krishna's love with the '' gopi'', Radha, in a rite of spring. This poem, which presen ...
(c. 950~1000 CE). Jayadeva pointed out that Brahmagupta's approach to solving equations of this type would yield infinitely large number of solutions, to which he then described a general method of solving such equations. Jayadeva's method was later refined by Bhāskara II in his ''
Bijaganita ''Bijaganita'' ( IAST: ') was treatise on algebra by the Indian mathematician Bhāskara II. It is the second volume of his main work '' Siddhānta Shiromani (''"Crown of treatises") alongside '' Lilāvati'', ''Grahaganita'' and ''Golādhyāya''.< ...
'' treatise to be known as the Chakravala method, ''
chakra Chakras (, ; sa , text=चक्र , translit=cakra , translit-std=IAST , lit=wheel, circle; pi, cakka) are various focal points used in a variety of ancient meditation practices, collectively denominated as Tantra, or the esoteric or ...
'' (derived from ''cakraṃ'' चक्रं) meaning 'wheel' in
Sanskrit Sanskrit (; attributively , ; nominally , , ) is a classical language belonging to the Indo-Aryan branch of the Indo-European languages. It arose in South Asia after its predecessor languages had diffused there from the northwest in the late ...
, relevant to the cyclic nature of the algorithm. With reference to the Chakravala method, E. O. Selenuis held that no European performances at the time of Bhāskara, nor much later, came up to its marvellous height of mathematical complexity.


1300

*
Madhava series In mathematics, a Madhava series or Leibniz series is any one of the series in a collection of infinite series expressions all of which are believed to have been discovered by an Indian Mathematician and Astronomer Madhava of Sangamagrama (c.&nbs ...
: The infinite series for π and for the trigonometric
sine In mathematics, sine and cosine are trigonometric functions of an angle. The sine and cosine of an acute angle are defined in the context of a right triangle: for the specified angle, its sine is the ratio of the length of the side that is oppo ...
, cosine, and
arctangent In mathematics, the inverse trigonometric functions (occasionally also called arcus functions, antitrigonometric functions or cyclometric functions) are the inverse functions of the trigonometric functions (with suitably restricted domains). Spec ...
is now attributed to Madhava of Sangamagrama (c. 1340 – 1425) and his Kerala school of astronomy and mathematics. He made use of the series expansion of to obtain an infinite series expression for π. Their rational approximation of the ''error'' for the finite sum of their series are of particular interest. They manipulated the error term to derive a faster converging series for π.They used the improved series to derive a rational expression, for π correct up to eleven decimal places, ''i.e.'' . Madhava of Sangamagrama and his successors at the
Kerala school of astronomy and mathematics The Kerala school of astronomy and mathematics or the Kerala school was a school of Indian mathematics, mathematics and Indian astronomy, astronomy founded by Madhava of Sangamagrama in Kingdom of Tanur, Tirur, Malappuram district, Malappuram, K ...
used geometric methods to derive large sum approximations for sine, cosine, and arctangent. They found a number of special cases of series later derived by Brook Taylor series. They also found the second-order Taylor approximations for these functions, and the third-order Taylor approximation for sine.


1500

* Seamless
celestial globe Celestial globes show the apparent positions of the stars in the sky. They omit the Sun, Moon, and planets because the positions of these bodies vary relative to those of the stars, but the ecliptic, along which the Sun moves, is indicated. The ...
: Considered one of the most remarkable feats in
metallurgy Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys. Metallurgy encompasses both the sc ...
, it was invented in
Kashmir Kashmir () is the northernmost geographical region of the Indian subcontinent. Until the mid-19th century, the term "Kashmir" denoted only the Kashmir Valley between the Great Himalayas and the Pir Panjal Range. Today, the term encompas ...
by Ali Kashmiri ibn Luqman in between 1589 and 1590 CE, and twenty other such
globe A globe is a spherical model of Earth, of some other celestial body, or of the celestial sphere. Globes serve purposes similar to maps, but unlike maps, they do not distort the surface that they portray except to scale it down. A model globe ...
s were later produced in
Lahore Lahore ( ; pnb, ; ur, ) is the second most populous city in Pakistan after Karachi and 26th most populous city in the world, with a population of over 13 million. It is the capital of the province of Punjab where it is the largest city. ...
and Kashmir during the Mughal Empire. Before they were rediscovered in the 1980s, it was believed by modern metallurgists to be technically impossible to produce metal globes without any seams, even with modern technology. These Mughal metallurgists pioneered the method of
lost-wax casting Lost-wax casting (also called "investment casting", "precision casting", or ''cire perdue'' which has been adopted into English from the French, ) is the process by which a duplicate metal sculpture (often silver, gold, brass, or bronze) is ...
in order to produce these globes.


1600

*
Prefabricated home Prefabricated homes, often referred to as prefab homes or simply prefabs, are specialist dwelling types of prefabricated building, which are manufactured off-site in advance, usually in standard sections that can be easily shipped and assembled. ...
and movable structure: The first prefabricated homes and movable structures were invented in 16th-century
Mughal India The Mughal Empire was an early-modern empire that controlled much of South Asia between the 16th and 19th centuries. Quote: "Although the first two Timurid emperors and many of their noblemen were recent migrants to the subcontinent, the d ...
by
Akbar Abu'l-Fath Jalal-ud-din Muhammad Akbar (25 October 1542 – 27 October 1605), popularly known as Akbar the Great ( fa, ), and also as Akbar I (), was the third Mughal emperor, who reigned from 1556 to 1605. Akbar succeeded his father, Hum ...
. These structures were reported by Arif Qandahari in 1579.


1700

*
Shampoo Shampoo () is a hair care product, typically in the form of a viscous liquid, that is used for cleaning hair. Less commonly, shampoo is available in solid bar format. Shampoo is used by applying it to wet hair, massaging the product into the ...
: The word ''
shampoo Shampoo () is a hair care product, typically in the form of a viscous liquid, that is used for cleaning hair. Less commonly, shampoo is available in solid bar format. Shampoo is used by applying it to wet hair, massaging the product into the ...
'' in English is derived from Hindustani (, ), and dates to 1762. A variety of herbs and their extracts were used as shampoos since ancient times in India. A very effective early shampoo was made by boiling
Sapindus ''Sapindus'' is a genus of about five to twelve species of shrubs and small trees in the lychee family, Sapindaceae, native to warm temperate to tropical regions of the world. The genus includes both deciduous and evergreen species. Members of ...
with dried
Indian gooseberry ''Phyllanthus emblica'', also known as emblic, emblic myrobalan, myrobalan, Indian gooseberry, Malacca tree, or amla, from the Sanskrit आमलकी (āmalakī), is a deciduous tree of the family Phyllanthaceae. Its native range is tropical a ...
(''aamla'') and a few other herbs, using the strained extract. Sapindus, also known as soapberries or soapnuts, is called (Sanskrit: ) in ancient Indian texts and its fruit pulp contain
saponin Saponins (Latin "sapon", soap + "-in", one of), also selectively referred to as triterpene glycosides, are bitter-tasting usually toxic plant-derived organic chemicals that have a foamy quality when agitated in water. They are widely distributed ...
s, a natural surfactant. The extract of creates a lather which Indian texts identify as (Sanskrit: ). which leaves the hair soft, shiny and manageable. Other products used for hair cleansing were shikakai (
Acacia concinna ''Senegalia rugata'' is a spiny climbing shrub native to China and tropical Asia, common in the warm plains of central and south India. It is renowned as a raw material for shampoo, and the leaves and young shoots are often eaten. Archaeobota ...
), soapnuts (
Sapindus ''Sapindus'' is a genus of about five to twelve species of shrubs and small trees in the lychee family, Sapindaceae, native to warm temperate to tropical regions of the world. The genus includes both deciduous and evergreen species. Members of ...
),
hibiscus ''Hibiscus'' is a genus of flowering plants in the mallow family, Malvaceae. The genus is quite large, comprising several hundred species that are native to warm temperate, subtropical and tropical regions throughout the world. Member species ...
flowers, ritha (
Sapindus mukorossi ''Sapindus mukorossi'', commonly known as Indian soapberry, washnut, or ritha, is a species of tree in the family Sapindaceae. It is a deciduous tree that grows in the lower foothills and midhills of the Himalayas at altitudes of up to . It is ...
) and arappu (Albizzia amara).
Guru Nanak Gurū Nānak (15 April 1469 – 22 September 1539; Gurmukhi: ਗੁਰੂ ਨਾਨਕ; pronunciation: , ), also referred to as ('father Nānak'), was the founder of Sikhism and is the first of the ten Sikh Gurus. His birth is celebrated wor ...
, the founding prophet and the first
Guru Guru ( sa, गुरु, IAST: ''guru;'' Pali'': garu'') is a Sanskrit term for a "mentor, guide, expert, or master" of certain knowledge or field. In pan-Indian traditions, a guru is more than a teacher: traditionally, the guru is a reverentia ...
of
Sikhism Sikhism (), also known as Sikhi ( pa, ਸਿੱਖੀ ', , from pa, ਸਿੱਖ, lit=disciple', 'seeker', or 'learner, translit=Sikh, label=none),''Sikhism'' (commonly known as ''Sikhī'') originated from the word ''Sikh'', which comes fro ...
, made references to soapberry tree and soap in 16th century. Cleansing with hair and body massage (''champu'') during daily strip wash was an indulgence of early colonial traders in India. When they returned to Europe, they introduced the newly learnt habits, including the hair treatment they called shampoo. *
Mysorean rockets Mysorean rockets were an Indian military weapon, the iron-cased rockets were successfully deployed for military use. The Mysorean army, under Hyder Ali and his son Tipu Sultan, used the rockets effectively against the British East India Company ...
: The first iron-cased and metal-cylinder
rocket A rocket (from it, rocchetto, , bobbin/spool) is a vehicle that uses jet propulsion to accelerate without using the surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entirely fr ...
s were developed by
Tipu Sultan Tipu Sultan (born Sultan Fateh Ali Sahab Tipu, 1 December 1751 – 4 May 1799), also known as the Tiger of Mysore, was the ruler of the Kingdom of Mysore based in South India. He was a pioneer of rocket artillery.Dalrymple, p. 243 He int ...
, ruler of the South Indian
Kingdom of Mysore The Kingdom of Mysore was a realm in South India, southern India, traditionally believed to have been founded in 1399 in the vicinity of the modern city of Mysore. From 1799 until 1950, it was a princely state, until 1947 in a subsidiary allia ...
, and his father
Hyder Ali Hyder Ali ( حیدر علی, ''Haidarālī''; 1720 – 7 December 1782) was the Sultan and ''de facto'' ruler of the Kingdom of Mysore in southern India. Born as Hyder Ali, he distinguished himself as a soldier, eventually drawing the att ...
, in the 1780s. He successfully used these iron-cased rockets against the larger forces of the
British East India Company The East India Company (EIC) was an English, and later British, joint-stock company founded in 1600 and dissolved in 1874. It was formed to trade in the Indian Ocean region, initially with the East Indies (the Indian subcontinent and Southea ...
during the
Anglo-Mysore Wars The Anglo-Mysore Wars were a series of four wars fought during the last three decades of the 18th century between the Kingdom of Mysore#Under Haider Ali and Tipu Sultan, Sultanate of Mysore on the one hand, and the British East India Company (r ...
. The Mysore rockets of this period were much more advanced than what the British had seen, chiefly because of the use of iron tubes for holding the propellant; this enabled higher thrust and longer range for the missile (up to 2 km range). After Tipu's eventual defeat in the
Fourth Anglo-Mysore War The Fourth Anglo-Mysore War was a conflict in South India between the Kingdom of Mysore against the British East India Company and the Hyderabad Deccan in 1798–99. This was the final conflict of the four Anglo-Mysore Wars. The British captured ...
and the capture of the Mysore iron rockets, they were influential in British rocket development, inspiring the
Congreve rocket The Congreve rocket was a type of rocket artillery designed by British inventor Sir William Congreve in 1808. The design was based upon the rockets deployed by the Kingdom of Mysore against the East India Company during the Second, Third, an ...
, and were soon put into use in the
Napoleonic Wars The Napoleonic Wars (1803–1815) were a series of major global conflicts pitting the French Empire and its allies, led by Napoleon I, against a fluctuating array of European states formed into various coalitions. It produced a period of Fren ...
.


1800

*
Microwave communication Microwave transmission is the transmission of information by electromagnetic waves with wavelengths in the microwave frequency range of 300MHz to 300GHz(1 m - 1 mm wavelength) of the electromagnetic spectrum. Microwave signals are normally li ...
: The first public demonstration of microwave transmission was made by
Jagadish Chandra Bose Sir Jagadish Chandra Bose (;, ; 30 November 1858 – 23 November 1937) was a biologist, physicist, Botany, botanist and an early writer of science fiction. He was a pioneer in the investigation of radio microwave optics, made significant contr ...
, in Calcutta, in 1895, two years before a similar demonstration by Marconi in England, and just a year after
Oliver Lodge Sir Oliver Joseph Lodge, (12 June 1851 – 22 August 1940) was a British physicist and writer involved in the development of, and holder of key patents for, radio. He identified electromagnetic radiation independent of Heinrich Rudolf Hertz, H ...
's commemorative lecture on Radio communication, following Hertz's death. * Iron and mercury coherer: In 1899, the
Bengali Bengali or Bengalee, or Bengalese may refer to: *something of, from, or related to Bengal, a large region in South Asia * Bengalis, an ethnic and linguistic group of the region * Bengali language, the language they speak ** Bengali alphabet, the w ...
physicist Sir
Jagdish Chandra Bose Sir Jagadish Chandra Bose (;, ; 30 November 1858 – 23 November 1937) was a biologist, physicist, botanist and an early writer of science fiction. He was a pioneer in the investigation of radio microwave optics, made significant contributions ...
announced the development of an "''iron-mercury-iron coherer with telephone detector''" in a paper presented at the Royal Society, London. He also later receive
U.S. Patent 755,840
"''Detector for electrical disturbances''" (1904), for a specific
electromagnetic In physics, electromagnetism is an interaction that occurs between particles with electric charge. It is the second-strongest of the four fundamental interactions, after the strong force, and it is the dominant force in the interactions of a ...
receiver.


1900

*
Boson In particle physics, a boson ( ) is a subatomic particle whose spin quantum number has an integer value (0,1,2 ...). Bosons form one of the two fundamental classes of subatomic particle, the other being fermions, which have odd half-integer s ...
: The name ''boson'' was coined by
Paul Dirac Paul Adrien Maurice Dirac (; 8 August 1902 – 20 October 1984) was an English theoretical physicist who is regarded as one of the most significant physicists of the 20th century. He was the Lucasian Professor of Mathematics at the Univer ...
to commemorate the contribution of the
Indian Indian or Indians may refer to: Peoples South Asia * Indian people, people of Indian nationality, or people who have an Indian ancestor ** Non-resident Indian, a citizen of India who has temporarily emigrated to another country * South Asia ...
physicist
Satyendra Nath Bose Satyendra Nath Bose (; 1 January 1894 – 4 February 1974) was a Bengali mathematician and physicist specializing in theoretical physics. He is best known for his work on quantum mechanics in the early 1920s, in developing the foundation for ...
. In
quantum mechanics Quantum mechanics is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles. It is the foundation of all quantum physics including quantum chemistry, ...
, a boson ({{IPAc-en, ˈ, b, oʊ, s, ɒ, n, ,_, ˈ, b, oʊ, z, ɒ, n) is a particle that follows
Bose–Einstein statistics In quantum statistics, Bose–Einstein statistics (B–E statistics) describes one of two possible ways in which a collection of non-interacting, indistinguishable particles may occupy a set of available discrete energy states at thermodynamic e ...
. Bosons make up one of the two classes of
particles In the physical sciences, a particle (or corpuscule in older texts) is a small localized object which can be described by several physical or chemical properties, such as volume, density, or mass. They vary greatly in size or quantity, from su ...
, the other being
fermion In particle physics, a fermion is a particle that follows Fermi–Dirac statistics. Generally, it has a half-odd-integer spin: spin , spin , etc. In addition, these particles obey the Pauli exclusion principle. Fermions include all quarks an ...
s. *
Raman effect Raman scattering or the Raman effect () is the inelastic scattering of photons by matter, meaning that there is both an exchange of energy and a change in the light's direction. Typically this effect involves vibrational energy being gained by a ...
: The Encyclopædia Britannica (2008) reports: "change in the wavelength of light that occurs when a light beam is deflected by molecules. The phenomenon is named for
Sir Chandrasekhara Venkata Raman Sir Chandrasekhara Venkata Raman (; 7 November 188821 November 1970) was an Indian physicist known for his work in the field of light scattering. Using a spectrograph that he developed, he and his student K. S. Krishnan discovered that when ...
, who discovered it in 1928. When a beam of light traverses a dust-free, transparent sample of a chemical compound, a small fraction of the light emerges in directions other than that of the incident (incoming) beam. Most of this scattered light is of unchanged wavelength. A small part, however, has wavelengths different from that of the incident light; its presence is a result of the Raman effect." *
Landau–Ramanujan constant In mathematics and the field of number theory, the Landau–Ramanujan constant is the positive real number ''b'' that occurs in a theorem proved by Edmund Landau in 1908, stating that for large x, the number of positive integers below x that are the ...
,
Mock theta function In mathematics, a mock modular form is the holomorphic part of a harmonic weak Maass form, and a mock theta function is essentially a mock modular form of weight . The first examples of mock theta functions were described by Srinivasa Ramanujan ...
s, Ramanujan conjecture,
Ramanujan prime In mathematics, a Ramanujan prime is a prime number that satisfies a result proven by Srinivasa Ramanujan relating to the prime-counting function. Origins and definition In 1919, Ramanujan published a new proof of Bertrand's postulate which, as ...
, Ramanujan–Soldner constant,
Ramanujan theta function In mathematics, particularly -analog theory, the Ramanujan theta function generalizes the form of the Jacobi theta functions, while capturing their general properties. In particular, the Jacobi triple product takes on a particularly elegant for ...
,
Ramanujan's sum In number theory, Ramanujan's sum, usually denoted ''cq''(''n''), is a function of two positive integer variables ''q'' and ''n'' defined by the formula : c_q(n) = \sum_ e^, where (''a'', ''q'') = 1 means that ''a'' only takes on values coprime ...
,
Rogers–Ramanujan identities In mathematics, the Rogers–Ramanujan identities are two identities related to basic hypergeometric series and partition (number theory), integer partitions. The identities were first discovered and proved by , and were subsequently rediscovered ( ...
,
Ramanujan's master theorem In mathematics, Ramanujan's Master Theorem, named after Srinivasa Ramanujan, is a technique that provides an analytic expression for the Mellin transform of an analytic function. The result is stated as follows: If a complex-valued function f(x) ...
: Discovered by the Indian mathematician,
Srinivasa Ramanujan Srinivasa Ramanujan (; born Srinivasa Ramanujan Aiyangar, ; 22 December 188726 April 1920) was an Indian mathematician. Though he had almost no formal training in pure mathematics, he made substantial contributions to mathematical analysis ...
. *
Chandrasekhar limit The Chandrasekhar limit () is the maximum mass of a stable white dwarf star. The currently accepted value of the Chandrasekhar limit is about (). White dwarfs resist gravitational collapse primarily through electron degeneracy pressure, compared ...
and
Chandrasekhar number The Chandrasekhar number is a dimensionless quantity used in magnetic convection to represent ratio of the Lorentz force to the viscosity. It is named after the Indian astrophysicist Subrahmanyan Chandrasekhar. The number's main function is as a m ...
: Discovered by and named after
Subrahmanyan Chandrasekhar Subrahmanyan Chandrasekhar (; ) (19 October 1910 – 21 August 1995) was an Indian-American theoretical physicist who spent his professional life in the United States. He shared the 1983 Nobel Prize for Physics with William A. Fowler for "... ...
, who received the
Nobel Prize in Physics ) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then " ...
in 1983 for his work on
stellar structure Stellar structure models describe the internal structure of a star in detail and make predictions about the luminosity, the color and the future evolution of the star. Different classes and ages of stars have different internal structures, reflec ...
and
stellar evolution Stellar evolution is the process by which a star changes over the course of time. Depending on the mass of the star, its lifetime can range from a few million years for the most massive to trillions of years for the least massive, which is cons ...
. *
Crescograph A crescograph is a device for measuring growth in plants. It was invented in the early 20th century by Sir Jagadish Chandra Bose. The Bose crescograph uses a series of clockwork gears and a smoked glass plate to record the movement of the tip of ...
: The crescograph, a device for measuring growth in plants, was invented in the early 20th century by the Bengali scientist Sir
Jagadish Chandra Bose Sir Jagadish Chandra Bose (;, ; 30 November 1858 – 23 November 1937) was a biologist, physicist, Botany, botanist and an early writer of science fiction. He was a pioneer in the investigation of radio microwave optics, made significant contr ...
. *
Pseudomonas putida ''Pseudomonas putida'' is a Gram-negative, rod-shaped, saprotrophic soil bacterium. Based on 16S rRNA analysis, ''P. putida'' was taxonomically confirmed to be a ''Pseudomonas'' species (''sensu stricto'') and placed, along with several other ...
: Indian (Bengali) inventor and microbiologist
Ananda Mohan Chakrabarty Ananda Mohan Chakrabarty ( bn, আনন্দমোহন চক্রবর্তী ''Ānandamōhan Cakrabartī''), PhD (4 April 1938 – 10 Jul 2020) was an Indian American microbiologist, scientist, and researcher, most notable for his w ...
created a species of man made micro organism to break down crude oil. He genetically engineered a new species of ''
Pseudomonas ''Pseudomonas'' is a genus of Gram-negative, Gammaproteobacteria, belonging to the family Pseudomonadaceae and containing 191 described species. The members of the genus demonstrate a great deal of metabolic diversity and consequently are able ...
''
bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...
("the
oil An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water) & lipophilic (mixes with other oils). Oils are usually flammable and surface active. Most oils are unsaturated ...
-eating bacteria") in 1971. United States Supreme Court granted Chakrabarty's invention patent even though it was a living species. The court ruling decreed that Chakrabarty's discovery was "not nature's handiwork, but his own..." The inventor Chakrabarty secured his patent in 1980(see
Diamond v. Chakrabarty ''Diamond v. Chakrabarty'', 447 U.S. 303 (1980), was a United States Supreme Court case dealing with whether living organisms can be patented. Writing for a five-justice majority, Chief Justice Warren E. Burger held that human-made bacteria could ...
) *
Yellapragada Subbarow Yellapragada Subba Rao (12 January 1895 – 8 August 1948) was a pioneering Indian biochemist who discovered the function of adenosine triphosphate (ATP) as an energy source in the cell, developed methotrexate for the treatment of cancer a ...
discovered the function of
adenosine triphosphate Adenosine triphosphate (ATP) is an organic compound that provides energy to drive many processes in living cells, such as muscle contraction, nerve impulse propagation, condensate dissolution, and chemical synthesis. Found in all known forms of ...
as an energy source in the
cell Cell most often refers to: * Cell (biology), the functional basic unit of life Cell may also refer to: Locations * Monastic cell, a small room, hut, or cave in which a religious recluse lives, alternatively the small precursor of a monastery w ...
, and developed
methotrexate Methotrexate (MTX), formerly known as amethopterin, is a chemotherapy agent and immune-system suppressant. It is used to treat cancer, autoimmune diseases, and ectopic pregnancies. Types of cancers it is used for include breast cancer, leuke ...
for the treatment of
cancer Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal b ...
. *
Har Gobind Khorana Har Gobind Khorana (9 January 1922 – 9 November 2011) was an Indian American biochemist. While on the faculty of the University of Wisconsin–Madison, he shared the 1968 Nobel Prize for Physiology or Medicine with Marshall W. Nirenberg and ...
was the first to demonstrate the role of
nucleotides Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules w ...
in
protein synthesis Protein biosynthesis (or protein synthesis) is a core biological process, occurring inside Cell (biology), cells, homeostasis, balancing the loss of cellular proteins (via Proteolysis, degradation or Protein targeting, export) through the product ...
. He shared the 1968
Nobel Prize for Physiology or Medicine The Nobel Prize in Physiology or Medicine is awarded yearly by the Nobel Assembly at the Karolinska Institute for outstanding discoveries in physiology or medicine. The Nobel Prize is not a single prize, but five separate prizes that, according ...
with
Marshall W. Nirenberg Marshall Warren Nirenberg (April 10, 1927 – January 15, 2010) was an American biochemist and geneticist. He shared a Nobel Prize in Physiology or Medicine in 1968 with Har Gobind Khorana and Robert W. Holley for "breaking the genetic code" an ...
and
Robert W. Holley Robert William Holley (January 28, 1922 – February 11, 1993) was an American biochemist. He shared the Nobel Prize in Physiology or Medicine in 1968 (with Har Gobind Khorana and Marshall Warren Nirenberg) for describing the structure of alani ...
for research that showed how the order of
nucleotides Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules w ...
in
nucleic acids Nucleic acids are biopolymers, macromolecules, essential to all known forms of life. They are composed of nucleotides, which are the monomers made of three components: a 5-carbon sugar, a phosphate group and a nitrogenous base. The two main clas ...
, which carry the
genetic code The genetic code is the set of rules used by living cells to translate information encoded within genetic material ( DNA or RNA sequences of nucleotide triplets, or codons) into proteins. Translation is accomplished by the ribosome, which links ...
of the cell, control the cell's synthesis of proteins. *
Abhyankar's conjecture In abstract algebra, Abhyankar's conjecture is a 1957 conjecture of Shreeram Abhyankar, on the Galois groups of algebraic function fields of characteristic ''p''. The soluble case was solved by Serre in 1990 and the full conjecture was proved i ...
,
Abhyankar's lemma In mathematics, Abhyankar's lemma (named after Shreeram Shankar Abhyankar) allows one to kill tame ramification by taking an extension of a base field. More precisely, Abhyankar's lemma states that if ''A'', ''B'', ''C'' are local fields such th ...
,
Abhyankar–Moh theorem In mathematics, the Abhyankar–Moh theorem states that if L is a complex line in the complex affine plane \mathbb^2, then every embedding of L into \mathbb^2 extends to an automorphism of the plane. It is named after Shreeram Shankar Abhyankar and ...
: Developed by
Shreeram Shankar Abhyankar Shreeram Shankar Abhyankar (22 July 1930 – 2 November 2012) was an Indian American mathematician known for his contributions to algebraic geometry. He, at the time of his death, held the Marshall Distinguished Professor of Mathematics Chair ...
. *
Saha ionization equation In physics, the Saha ionization equation is an expression that relates the ionization state of a gas in thermal equilibrium to the temperature and pressure. The equation is a result of combining ideas of quantum mechanics and statistical mechanics ...
: The Saha equation, derived by the Bengali scientist
Meghnad Saha Meghnad Saha (6 October 1893 – 16 February 1956) was an Indian astrophysicist who developed the Saha ionization equation, used to describe chemical and physical conditions in stars. His work allowed astronomers to accurately relate the sp ...
(6 October 1893 – 16 February 1956) in 1920, conceptualizes
ionization Ionization, or Ionisation is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons, often in conjunction with other chemical changes. The resulting electrically charged atom or molecule i ...
s in context of stellar atmospheres. * Basu's theorem: The Basu's theorem, a result of
Debabrata Basu Debabrata Basu (5 July 1924 – 24 March 2001) was an Indian statistician who made fundamental contributions to the foundations of statistics. Basu invented simple examples that displayed some difficulties of likelihood-based statistics and ...
(1955) states that any complete sufficient statistic is independent of any ancillary statistic. * Visceral leishmaniasis, treatment of: The Indian (Bengali) medical practitioner
Upendranath Brahmachari Rai Bahadur Sir Upendranath Brahmachari ( bn, উপেন্দ্রনাথ ব্রহ্মচারী) (19 December 1873 – 6 February 1946) was a leading Indian physician and scientist of his time. He synthesised Urea-Stibamine (car ...
(19 December 1873 – 6 February 1946) was nominated for the
Nobel Prize in Physiology or Medicine The Nobel Prize in Physiology or Medicine is awarded yearly by the Nobel Assembly at the Karolinska Institute for outstanding discoveries in physiology or medicine. The Nobel Prize is not a single prize, but five separate prizes that, accord ...
in 1929 for his discovery of 'ureastibamine (
antimonial Antimonials, in pre-modern medicine, were remedies principally containing antimony, used chiefly for emetic purposes. They might also have qualified for cathartic, diaphoretic, or simply alternative uses. Such treatments were considered unparall ...
compound Compound may refer to: Architecture and built environments * Compound (enclosure), a cluster of buildings having a shared purpose, usually inside a fence or wall ** Compound (fortification), a version of the above fortified with defensive struct ...
for treatment of
kala azar Visceral leishmaniasis (VL), also known as kala-azar (Hindi: kālā āzār, "black sickness") or "black fever", is the most severe form of leishmaniasis and, without proper diagnosis and treatment, is associated with high fatality. Leishmaniasi ...
) and a new disease, post-kalaazar dermal leishmanoid.' Brahmachari's cure for Visceral leishmaniasis was the urea salt of para-amino-phenyl stibnic acid which he called Urea Stibamine. Following the discovery of Urea Stibamine, Visceral leishmaniasis was largely eradicated from the world, except for some underdeveloped regions. *
Raychaudhuri equation In general relativity, the Raychaudhuri equation, or Landau–Raychaudhuri equation, is a fundamental result describing the motion of nearby bits of matter. The equation is important as a fundamental lemma for the Penrose–Hawking singularity the ...
: Discovered by the
Bengali Bengali or Bengalee, or Bengalese may refer to: *something of, from, or related to Bengal, a large region in South Asia * Bengalis, an ethnic and linguistic group of the region * Bengali language, the language they speak ** Bengali alphabet, the w ...
physicist
Amal Kumar Raychaudhuri Amal Kumar Raychaudhuri (14 September 1923 – 18 June 2005) was an Indian physicist, known for his research in general relativity and cosmology. His most significant contribution is the eponymous Raychaudhuri equation, which demonstrates that ...
in 1954. This was a key ingredient of the Penrose-Hawking singularity theorems of
general relativity General relativity, also known as the general theory of relativity and Einstein's theory of gravity, is the geometric theory of gravitation published by Albert Einstein in 1915 and is the current description of gravitation in modern physics ...
. * Ajay V. Bhatt, an Indian-
American American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, pe ...
computer architect, helped define and develop several widely used technologies, including USB (Universal Serial Bus), AGP (Accelerated Graphics Port),
PCI Express PCI Express (Peripheral Component Interconnect Express), officially abbreviated as PCIe or PCI-e, is a high-speed serial computer expansion bus standard, designed to replace the older PCI, PCI-X and AGP bus standards. It is the common ...
, Platform Power management architecture and various chipset improvements. IVF fertilization- Done for the first time by dr subhash mukhopadhyay in kolkata using primitive technology


2000

*
J Sharp Visual J# (pronounced "jay-sharp") is a discontinued implementation of the J# programming language that was a transitional language for programmers of Java and Visual J++ languages, so they could use their existing knowledge and applications wi ...
: Visual J# (pronounced "jay-
sharp Sharp or SHARP may refer to: Acronyms * SHARP (helmet ratings) (Safety Helmet Assessment and Rating Programme), a British motorcycle helmet safety rating scheme * Self Help Addiction Recovery Program, a charitable organisation founded in 199 ...
")
programming language A programming language is a system of notation for writing computer programs. Most programming languages are text-based formal languages, but they may also be graphical. They are a kind of computer language. The description of a programming ...
was a transitional language for programmers of
Java Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's List ...
and
Visual J++ Visual J++ is Microsoft's discontinued implementation of Java. Syntax, keywords, and grammatical conventions were the same as Java's. It was introduced in 1996 and discontinued in January 2004, replaced to a certain extent by J# and C#. The i ...
languages, so they could use their existing knowledge and applications on
.NET Framework The .NET Framework (pronounced as "''dot net"'') is a proprietary software framework developed by Microsoft that runs primarily on Microsoft Windows. It was the predominant implementation of the Common Language Infrastructure (CLI) until bein ...
.It was developed by the
Hyderabad Hyderabad ( ; , ) is the capital and largest city of the Indian state of Telangana and the ''de jure'' capital of Andhra Pradesh. It occupies on the Deccan Plateau along the banks of the Musi River (India), Musi River, in the northern part ...
-based Microsoft India Development Center at HITEC City in India. *
Kojo (programming language) Kojo is a programming language and integrated development environment (IDE) for computer programming and learning. It has many different features that enable playing, exploring, creating, and learning in the areas of computer programming, mental s ...
: Kojo is a
programming language A programming language is a system of notation for writing computer programs. Most programming languages are text-based formal languages, but they may also be graphical. They are a kind of computer language. The description of a programming ...
and
integrated development environment An integrated development environment (IDE) is a software application that provides comprehensive facilities to computer programmers for software development. An IDE normally consists of at least a source code editor, build automation tools a ...
(IDE) for computer programming and learning. Kojo is
open-source software Open-source software (OSS) is computer software that is released under a license in which the copyright holder grants users the rights to use, study, change, and distribute the software and its source code to anyone and for any purpose. Op ...
. It was created, and is actively developed, by Lalit Pant, a computer programmer and teacher living in
Dehradun, India Dehradun () is the capital and the List of cities in Uttarakhand by population, most populous city of the Indian state of Uttarakhand. It is the administrative headquarters of the eponymous Dehradun district, district and is governed by the Dehr ...
. *
Lunar water Lunar water is water that is present on the Moon. Diffuse water molecules can persist at the Moon's sunlit surface, as discovered by NASA's SOFIA observatory in 2020. Gradually water vapor is decomposed by sunlight, leaving hydrogen and oxyg ...
: Although the presence of water ice on the moon has been conjectured by various scientists since the 1960s, inconclusive evidence of free water ice had also been identified the first incontrovertible evidence of water on the moon was provided by the payload Chace carried by the
Moon Impact Probe The Moon Impact Probe (MIP) developed by the Indian Space Research Organisation, Indian Space Research Organisation (ISRO), India's national space agency, was a moon, lunar probe that was released by ISRO's Chandrayaan-1 Exploration of the Moon, ...
released by
Chandrayaan-1 Chandrayaan-1 (, ) was the first Indian lunar probe under the Chandrayaan program. It was launched by the Indian Space Research Organisation in October 2008, and operated until August 2009. The mission included a lunar orbiter and an impacto ...
confirmed and established by
NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding t ...
.


See also

*
History of science and technology in India The history of science and technology in the Indian subcontinent begins with the prehistoric human activity of the Indus Valley Civilization to the early Indian states and empires. Prehistory By 5500 BCE a number of sites similar to Mehrgarh ...
* Nalanda University *
List of Indian inventions and discoveries This list of Indian inventions and discoveries details the inventions, scientific discoveries and contributions of India, including the ancient, classical and post-classical nations in the subcontinent historically referred to as India and th ...
*
Timeline of historic inventions The timeline of historic inventions is a chronological list of particularly important or significant technological inventions and their inventors, where known. Paleolithic The dates listed in this section refer to the earliest evidence of an i ...
Indian history timelines Indian inventions