A system of measurement is a collection of

units of measurement A unit of measurement is a definite magnitude (mathematics), magnitude of a quantity, defined and adopted by convention or by law, that is used as a standard for measurement of the same kind of quantity. Any other quantity of that kind can ...

and rules relating them to each other. Systems of measurement have historically been important, regulated and defined for the purposes of

science Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earliest archeological evidence for ...

and

commerce Commerce is the large-scale organized system of activities, functions, procedures and institutions directly and indirectly related to the exchange (buying and selling) of goods and services among two or more parties within local, regional, nation ...

. Systems of measurement in use include the

International System of Units The International System of Units, known by the international abbreviation SI in all languages and sometimes pleonastically as the SI system, is the modern form of the metric system and the world's most widely used system of measurement. E ...

or (the modern form of the

metric system The metric system is a system of measurement that succeeded the Decimal, decimalised system based on the metre that had been introduced in French Revolution, France in the 1790s. The historical development of these systems culminated in the d ...

), the

British imperial system The imperial system of units, imperial system or imperial units (also known as British Imperial or Exchequer Standards of 1826) is the system of units first defined in the British Weights and Measures Act 1824 and continued to be developed thro ...

, and the

United States customary system United States customary units form a system of Units of measurement, measurement units commonly used in the United States and Territories of the United States, U.S. territories since being standardized and adopted in 1832. The United States cust ...

History

The

French Revolution The French Revolution ( ) was a period of radical political and societal change in France that began with the Estates General of 1789 and ended with the formation of the French Consulate in November 1799. Many of its ideas are considere ...

gave rise to the

, and this has spread around the world, replacing most customary units of measure. In most systems,

length Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the Interna ...

(distance),

mass Mass is an intrinsic property of a body. It was traditionally believed to be related to the quantity of matter in a physical body, until the discovery of the atom and particle physics. It was found that different atoms and different elementar ...

, and

time Time is the continued sequence of existence and events that occurs in an apparently irreversible succession from the past, through the present, into the future. It is a component quantity of various measurements used to sequence events, to ...

are ''base quantities''. Later science developments showed that an electromagnetic quantity such as

electric charge Electric charge is the physical property of matter that causes charged matter to experience a force when placed in an electromagnetic field. Electric charge can be ''positive'' or ''negative'' (commonly carried by protons and electrons respe ...

or electric current could be added to extend the set of base quantities.

Gaussian units Gaussian units constitute a metric system of physical units. This system is the most common of the several electromagnetic unit systems based on cgs (centimetre–gram–second) units. It is also called the Gaussian unit system, Gaussian-cgs unit ...

have only length, mass, and time as base quantities, with no separate electromagnetic dimension. Other quantities, such as

power Power most often refers to: * Power (physics), meaning "rate of doing work" ** Engine power, the power put out by an engine ** Electric power * Power (social and political), the ability to influence people or events ** Abusive power Power may a ...

and

speed In everyday use and in kinematics, the speed (commonly referred to as ''v'') of an object is the magnitude of the change of its position over time or the magnitude of the change of its position per unit of time; it is thus a scalar quanti ...

, are derived from the base set: for example, speed is distance per unit time. Historically a wide range of units was used for the same type of quantity: in different contexts, length was measured in

inch Measuring tape with inches The inch (symbol: in or ″) is a unit of length in the British imperial and the United States customary systems of measurement. It is equal to yard or of a foot. Derived from the Roman uncia ("twelfth") ...

es,

feet The foot ( : feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg made ...

yards The yard (symbol: yd) is an English unit of length in both the British imperial and US customary systems of measurement equalling 3 feet or 36 inches. Since 1959 it has been by international agreement standardized as exactly 0.914 ...

fathom A fathom is a unit of length in the imperial and the U.S. customary systems equal to , used especially for measuring the depth of water. The fathom is neither an International Standard (SI) unit, nor an internationally-accepted non-SI unit. Hi ...

s, rods,

chains A chain is a serial assembly of connected pieces, called links, typically made of metal, with an overall character similar to that of a rope in that it is flexible and curved in compression but linear, rigid, and load-bearing in tension. A c ...

furlong A furlong is a measure of distance in imperial units and United States customary units equal to one eighth of a mile, equivalent to 660 feet, 220 yards, 40 rods, 10 chains or approximately 201 metres. It is now mostly confined to use in hors ...

mile The mile, sometimes the international mile or statute mile to distinguish it from other miles, is a British imperial unit and United States customary unit of distance; both are based on the older English unit of length equal to 5,280 English ...

nautical mile A nautical mile is a unit of length used in air, marine, and space navigation, and for the definition of territorial waters. Historically, it was defined as the meridian arc length corresponding to one minute ( of a degree) of latitude. Today ...

stadia Stadia may refer to: * One of the plurals of stadium, along with "stadiums" * The plural of stadion, an ancient Greek unit of distance, which equals to 600 Greek feet (''podes''). * Stadia (Caria), a town of ancient Caria, now in Turkey * Stadi ...

, leagues, with conversion factors that were not powers of ten. The preference for a more universal and consistent system only gradually spread with the growth of international trade and science. Changing a measurement system has costs in the near term, which results in resistance to such a change. The substantial benefit of conversion to a more rational and internationally consistent system of measurement has been recognized and promoted by scientists, engineers and politicians, and has resulted in most of the world adopting a commonly agreed metric system. In antiquity, ''systems of measurement'' were defined locally: the different units might be defined independently according to the length of a king's thumb or the size of his foot, the length of stride, the length of arm, or maybe the weight of water in a keg of specific size, perhaps itself defined in ''hands'' and ''knuckles''. The unifying characteristic is that there was some definition based on some standard. Eventually ''

cubit The cubit is an ancient unit of length based on the distance from the elbow to the tip of the middle finger. It was primarily associated with the Sumerians, Egyptians, and Israelites. The term ''cubit'' is found in the Bible regarding No ...

s'' and '' strides'' gave way to "customary units" to meet the needs of merchants and scientists. In the metric system and other recent systems, underlying relationships between quantities, as expressed by formulae of physics such as

Newton's laws of motion Newton's laws of motion are three basic laws of classical mechanics that describe the relationship between the motion of an object and the forces acting on it. These laws can be paraphrased as follows: # A body remains at rest, or in moti ...

, is used to select a small number of base quantities for which a unit is defined for each, from which all other units may be derived. Secondary units (multiples and submultiples) are derived from these base and derived units by multiplying by powers of ten, so for example where the unit of length is the

metre The metre (British spelling) or meter (American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its pref ...

; a distance of 1 m is 1,000 millimetres, or 0.001 kilometres.

Current practice

Metrication is complete or nearly complete in almost all countries.

US customary units United States customary units form a system of measurement units commonly used in the United States and U.S. territories since being standardized and adopted in 1832. The United States customary system (USCS or USC) developed from English units ...

are heavily used in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

and to some degree in

Liberia Liberia (), officially the Republic of Liberia, is a country on the West African coast. It is bordered by Sierra Leone to Liberia–Sierra Leone border, its northwest, Guinea to its north, Ivory Coast to its east, and the Atlantic Ocean ...

. Traditional

Burmese units of measurement The traditional Burmese units of measurement were a system of measurement used in Myanmar (also known as Burma). According to the 2010 CIA Factbook, Myanmar is one of three countries that have not adopted the International System of Units (SI ...

are used in

Burma Myanmar, ; UK pronunciations: US pronunciations incl. . Note: Wikipedia's IPA conventions require indicating /r/ even in British English although only some British English speakers pronounce r at the end of syllables. As John Wells explai ...

. U.S. units are used in limited contexts in Canada due to the large volume of trade; there is also considerable use of imperial weights and measures, despite ''de jure'' Canadian conversion to metric. A number of other jurisdictions have laws mandating or permitting other systems of measurement in some or all contexts, such as the United Kingdom – whose road signage legislation, for instance, only allows distance signs displaying

imperial units The imperial system of units, imperial system or imperial units (also known as British Imperial or Exchequer Standards of 1826) is the system of units first defined in the British Weights and Measures Act 1824 and continued to be developed thro ...

(miles or yards) – or Hong Kong.HK Weights and Measures Ordinance
/ref> In the United States, metric units are used almost universally in science, widely in the military, and partially in industry, but customary units predominate in household use. At retail stores, the litre (spelled 'liter' in the U.S.) is a commonly used unit for volume, especially on bottles of beverages, and milligrams, rather than grains, are used for medications. Some other non- SI units are still in international use, such as

s and

knots A knot is a fastening in rope or interwoven lines. Knot may also refer to: Places * Knot, Nancowry, a village in India Archaeology * Knot of Isis (tyet), symbol of welfare/life. * Minoan snake goddess figurines#Sacral knot Arts, entertainme ...

in aviation and shipping.

Metric system

Metric system The metric system is a system of measurement that succeeded the Decimal, decimalised system based on the metre that had been introduced in French Revolution, France in the 1790s. The historical development of these systems culminated in the d ...

s of units have evolved since the adoption of the first well-defined system in France in 1795. During this evolution the use of these systems has spread throughout the world, first to non-English-speaking countries, and then to English speaking countries. Multiples and submultiples of metric units are related by powers of ten and their names are formed with

prefixes A prefix is an affix which is placed before the Word stem, stem of a word. Adding it to the beginning of one word changes it into another word. For example, when the prefix ''un-'' is added to the word ''happy'', it creates the word ''unhappy'' ...

. This relationship is compatible with the decimal system of numbers and it contributes greatly to the convenience of metric units. In the early metric system there were two base units, the

for length and the

gram The gram (originally gramme; SI unit symbol g) is a Physical unit, unit of mass in the International System of Units (SI) equal to one one thousandth of a kilogram. Originally defined as of 1795 as "the absolute weight of a volume of pure wate ...

for mass. The other units of length and mass, and all units of area, volume, and derived units such as density were derived from these two base units.

Mesures usuelles Mesures usuelles (, ''customary measurements'') were a French system of measurement introduced by Napoleon I in 1812 to act as compromise between the metric system and traditional measurements. The system was restricted to use in the retail indust ...

( French for ''customary measurements'') were a system of measurement introduced as a compromise between the metric system and traditional measurements. It was used in France from 1812 to 1839. A number of variations on the metric system have been in use. These include gravitational systems, the centimetre–gram–second systems (cgs) useful in science, the metre–tonne–second system (mts) once used in the USSR and the metre–kilogram–second system (mks). In some engineering fields, like

computer-aided design Computer-aided design (CAD) is the use of computers (or ) to aid in the creation, modification, analysis, or optimization of a design. This software is used to increase the productivity of the designer, improve the quality of design, improve c ...

, millimetre–gram–second (mmgs) is also used. The current international standard for the metric system is the

( or SI). It is a system in which all units can be expressed in terms of seven units. The units that serves as the

SI base unit The SI base units are the standard units of measurement defined by the International System of Units (SI) for the seven base quantities of what is now known as the International System of Quantities: they are notably a basic set from which all ...

s are the

kilogram The kilogram (also kilogramme) is the unit of mass in the International System of Units (SI), having the unit symbol kg. It is a widely used measure in science, engineering and commerce worldwide, and is often simply called a kilo colloquially ...

second The second (symbol: s) is the unit of time in the International System of Units (SI), historically defined as of a day – this factor derived from the division of the day first into 24 hours, then to 60 minutes and finally to 60 seconds ...

ampere The ampere (, ; symbol: A), often shortened to amp,SI supports only the use of symbols and deprecates the use of abbreviations for units. is the unit of electric current in the International System of Units (SI). One ampere is equal to elect ...

kelvin The kelvin, symbol K, is the primary unit of temperature in the International System of Units (SI), used alongside its prefixed forms and the degree Celsius. It is named after the Belfast-born and University of Glasgow-based engineer and phys ...

mole Mole (or Molé) may refer to: Animals * Mole (animal) or "true mole", mammals in the family Talpidae, found in Eurasia and North America * Golden moles, southern African mammals in the family Chrysochloridae, similar to but unrelated to Talpida ...

, and

candela The candela ( or ; symbol: cd) is the unit of luminous intensity in the International System of Units (SI). It measures luminous power per unit solid angle emitted by a light source in a particular direction. Luminous intensity is analogous to ...

Imperial and US customary units

Both

imperial unit The imperial system of units, imperial system or imperial units (also known as British Imperial or Exchequer Standards of 1826) is the system of units first defined in the British Weights and Measures Act 1824 and continued to be developed thro ...

s and

derive from earlier

English unit English units are the units of measurement used in England up to 1826 (when they were replaced by Imperial units), which evolved as a combination of the Anglo-Saxon and Roman systems of units. Various standards have applied to English units at d ...

s. Imperial units were mostly used in the former

British Empire The British Empire was composed of the dominions, colonies, protectorates, mandates, and other territories ruled or administered by the United Kingdom and its predecessor states. It began with the overseas possessions and trading posts esta ...

and the

British Commonwealth The Commonwealth of Nations, simply referred to as the Commonwealth, is a political association of 56 member states, the vast majority of which are former territories of the British Empire. The chief institutions of the organisation are the Co ...

, but in all these countries they have been largely supplanted by the metric system. They are still used for some applications in the United Kingdom but have been mostly replaced by the metric system in

commercial Commercial may refer to: * a dose of advertising conveyed through media (such as - for example - radio or television) ** Radio advertisement ** Television advertisement * (adjective for:) commerce, a system of voluntary exchange of products and s ...

scientific Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earliest archeological evidence for ...

, and

industrial Industrial may refer to: Industry * Industrial archaeology, the study of the history of the industry * Industrial engineering, engineering dealing with the optimization of complex industrial processes or systems * Industrial city, a city dominate ...

applications. US customary units, however, are still the main system of measurement in the

. While some steps towards

metrication Metrication or metrification is the act or process of converting to the metric system of measurement. All over the world, countries have transitioned from local and traditional units of measurement to the metric system. This process began in F ...

have been made (mainly in the late 1960s and early 1970s), the customary units have a strong hold due to the vast industrial infrastructure and commercial development. While imperial and US customary systems are closely related, there are a number of differences between them. Units of length and area (the

foot The foot ( : feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is a separate organ at the terminal part of the leg made ...

yard The yard (symbol: yd) is an English unit of length in both the British imperial and US customary systems of measurement equalling 3 feet or 36 inches. Since 1959 it has been by international agreement standardized as exactly 0.914 ...

, etc.) have been identical since the adoption of the International Yard and Pound Agreement; however, America and, formerly, India retained older definitions for surveying purposes. This gave rise to the US survey foot for instance. The

avoirdupois The avoirdupois system (; abbreviated avdp.) is a measurement system of weights that uses pounds and ounces as units. It was first commonly used in the 13th century AD and was updated in 1959. In 1959, by international agreement, the definiti ...

units of mass and weight differ for units larger than a pound (lb). The imperial system uses a stone of 14 lb, a long

hundredweight The hundredweight (abbreviation: cwt), formerly also known as the centum weight or quintal, is a British imperial and US customary unit of weight or mass. Its value differs between the US and British imperial systems. The two values are distingu ...

of 112 lb and a long

ton Ton is the name of any one of several units of measure. It has a long history and has acquired several meanings and uses. Mainly it describes units of weight. Confusion can arise because ''ton'' can mean * the long ton, which is 2,240 pounds ...

of 2240 lb. The stone is not used in the US and the hundredweights and tons are short: 100 lb and 2000 lb respectively. Where these systems most notably differ is in their units of volume. A US

fluid ounce A fluid ounce (abbreviated fl oz, fl. oz. or oz. fl., old forms ℥, fl ℥, f℥, ƒ ℥) is a unit of volume (also called ''capacity'') typically used for measuring liquids. The British Imperial, the United States customary, and the United St ...

(fl oz), about 29.6

millilitre The litre (international spelling) or liter (American English spelling) (SI symbols L and l, other symbol used: ℓ) is a metric unit of volume. It is equal to 1 cubic decimetre (dm3), 1000 cubic centimetres (cm3) or 0.001 cubic metre (m3). ...

s (ml), is slightly larger than the imperial fluid ounce (about 28.4 ml). However, as there are 16 US fl oz to a US

pint The pint (, ; symbol pt, sometimes abbreviated as ''p'') is a unit of volume or capacity in both the imperial unit, imperial and United States customary units, United States customary measurement systems. In both of those systems it is tradition ...

and 20 imp fl oz per imperial pint, the imperial pint is about 20% larger. The same is true of

quart The quart (symbol: qt) is an English unit of volume equal to a quarter gallon. Three kinds of quarts are currently used: the liquid quart and dry quart of the US customary system and the of the British imperial system. All are roughly equal ...

gallon The gallon is a unit of volume in imperial units and United States customary units. Three different versions are in current use: *the imperial gallon (imp gal), defined as , which is or was used in the United Kingdom, Ireland, Canada, Austral ...

s, etc.; six US gallons are a little less than five imperial gallons. The

system served as the general system of mass and weight. In addition to this there are the

troy Troy ( el, Τροία and Latin: Troia, Hittite language, Hittite: 𒋫𒊒𒄿𒊭 ''Truwiša'') or Ilion ( el, Ίλιον and Latin: Ilium, Hittite language, Hittite: 𒃾𒇻𒊭 ''Wiluša'') was an ancient city located at Hisarlik in prese ...

and the

apothecaries' system The apothecaries' system, or apothecaries' weights and measures, is a historical system of mass and volume units that were used by physicians and apothecaries for medical prescriptions and also sometimes by scientists."Medicinal-Gewicht, Apotheke ...

s. Troy weight was customarily used for

precious metal Precious metals are rare, naturally occurring metallic chemical elements of high economic value. Chemically, the precious metals tend to be less reactive than most elements (see noble metal). They are usually ductile and have a high lustre. ...

black powder Gunpowder, also commonly known as black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur, carbon (in the form of charcoal) and potassium nitrate (saltpeter). Th ...

and

gemstone A gemstone (also called a fine gem, jewel, precious stone, or semiprecious stone) is a piece of mineral crystal which, in cut and polished form, is used to make jewelry or other adornments. However, certain rocks (such as lapis lazuli, opal, ...

s. The troy ounce is the only unit of the system in current use; it is used for precious metals. Although the troy ounce is larger than its avoirdupois equivalent, the pound is smaller. The obsolete troy pound was divided into 12 ounces, rather than the 16 ounces per pound of the avoirdupois system. The apothecaries' system was traditionally used in

pharmacology Pharmacology is a branch of medicine, biology and pharmaceutical sciences concerned with drug or medication action, where a drug may be defined as any artificial, natural, or endogenous (from within the body) molecule which exerts a biochemica ...

, but has now been replaced by the metric system; it shared the same pound and ounce as the troy system but with different further subdivisions.

Natural units

Natural units In physics, natural units are physical units of measurement in which only universal physical constants are used as defining constants, such that each of these constants acts as a Coherence (units of measurement), coherent unit of a quantity. For e ...

are

defined in terms of universal

physical constants A physical constant, sometimes fundamental physical constant or universal constant, is a physical quantity that is generally believed to be both universal in nature and have constant value in time. It is contrasted with a mathematical constant, ...

in such a manner that selected physical constants take on the numerical value of one when expressed in terms of those units. Natural units are so named because their definition relies on only properties of

nature Nature, in the broadest sense, is the physics, physical world or universe. "Nature" can refer to the phenomenon, phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. ...

and not on any human construct. Varying systems of natural units are possible, depending on the choice of constants used. Some examples are as follows: *

Geometrized unit system A geometrized unit system, geometric unit system or geometrodynamic unit system is a system of natural units in which the base physical units are chosen so that the speed of light in vacuum, ''c'', and the gravitational constant, ''G'', are set eq ...

s are useful in

relativistic physics In physics, relativistic mechanics refers to mechanics compatible with special relativity (SR) and general relativity (GR). It provides a non-quantum mechanics, quantum mechanical description of a system of particles, or of a fluid, in cases where ...

. In these systems,

speed of light The speed of light in vacuum, commonly denoted , is a universal physical constant that is important in many areas of physics. The speed of light is exactly equal to ). According to the special theory of relativity, is the upper limit ...

and the gravitational constant are among the constants chosen. * Planck units is system of geometrized units in which the reduced Planck constant is included in the list of defining constants. It is based on only properties of free space rather than of any object or particle. * Stoney units is a system of geometrized units in which the Coulomb constant and the elementary charge are included. * Hartree atomic units are a system of units used in atomic physics, particularly for describing the properties of electrons. The atomic units have been chosen to use several constants relating to the electron: the electron mass, the elementary charge, the Coulomb constant and the reduced Planck constant. The unit of energy in this system is the total energy of the electron in the Bohr atom and called the Hartree energy. The unit of length is the Bohr radius.

Non-standard units

List of unusual units of measurement, Non-standard measurement units also found in books, newspapers etc., include:

Area

* The American football#Field and players, American football field, which has a playing area long by wide. This is often used by the United States, American public media for the sizes of large buildings or parks. It is used both as a unit of length (, the length of the playing field excluding goal areas) and as a unit of area (), about . * British media also frequently uses the Association football pitch, football pitch for equivalent purposes, although soccer pitches are not of a fixed size, but instead can vary within defined limits ( long, and wide, giving an area of ). However the UEFA Champions League field must be exactly giving an area of or . For example, "High-speed Sea Service, HSS vessels are aluminium catamarans about the size of a football pitch." * Larger areas are also expressed as a multiple of the areas of certain American states, or subdivisions of the UK etc.

Energy

* A ton of TNT equivalent, and its multiples the kiloton, the megaton, and the gigaton. Often used in stating the power of very energetic events such as explosions and volcanic events and earthquakes and asteroid impacts. A

of TNT as a unit of energy has been defined as 1000 thermochemical calories (). * The Little Boy, atom bomb dropped on Hiroshima. Its energy yield is often used in the public media and popular books as a unit of energy. (Its yield was roughly 13 kilotons, or 60 TJ.) * One stick of dynamite.

Units of currency

A unit of measurement that applies to money is called a unit of account in economics and unit of measure in accounting. This is normally a currency issued by a country or a fraction thereof; for instance, the United States dollar, US dollar and US cent ( of a dollar), or the euro and euro cent. ISO 4217 is the international standard describing three letter codes (also known as the currency code) to define the names of currencies established by the International Organization for Standardization (ISO).

Historical systems of measurement

Throughout history, many official systems of measurement have been used. While no longer in official use, some of these customary systems are occasionally used in day-to-day life, for instance in cooking.

Africa

* Algerian units of measurement, Algerian * Egyptian units of measurement, Egyptian * Ethiopian units of measurement, Ethiopian * Eritrean units of measurement, Eritrean * Guinean units of measurement, Guinean * Libyan units of measurements, Libyan * Malagasy units of measurement, Malagasy * Mauritian units of measurement, Mauritian * Moroccan units of measurement, Moroccan * Seychellois units of measurement, Seychellois * Somalian units of measurement, Somalian * Tunisian units of measurement, Tunisian * South African units of measurement, South African * Tanzanian units of measurement, Tanzanian

Asia

* Ancient Arabic weights and measures, ArabicM. Ismail Marcinkowski, ''Measures and Weights in the Islamic World. An English Translation of Professor Walther Hinz's Handbook "Islamische Maße und Gewichte"'', with a foreword by Professor Bosworth, F.B.A. Kuala Lumpur, ISTAC, 2002, . This work is an annotated translation of a work in German by the late German orientalist Walther Hinz, published in the ''Handbuch der Orientalistik'', erste Abteilung, Ergänzungsband I, Heft 1, Leiden, The Netherlands: E. J. Brill, 1970. * Afghan units of measurement, Afgan * Cambodian units of measurement, Cambodian * Chinese units of measurement, Chinese * Ancient Hebrew weights and measures, Hebrew (Bible, Biblical and Talmudic) * Hindu units of measurement, Hindu * Indonesian units of measurement, Indonesian * Japanese units of measurement, Japanese * Korean units of measurement, Korean * Omani units of measurement, Omani * History of measurement systems in Pakistan, Pakistani * Philippine units of measurement, Philippine * Ancient Mesopotamian weights and measures, Mesopotamian * Ancient Persian weights and measures, Persian * Singaporean units of measurement, Singaporean * Sri Lankan units of measurement, Sri Lankan * Syrian units of measurement, Syrian * Taiwanese units of measurement, Taiwanese * Tamil units of measurement, Tamil * Thai units of measurement, Thai * Vietnamese units of measurement, Vietnamese * Nepalese units of measurement, Nepalese Still in use: * Myanmar units of measurement, Myanmar

Europe

* Ancient Greek units of measurement, Ancient Greek * Belgian units of measurement, Belgian * Byzantine units of measurement, Byzantine * Czech units of measurement, Czech * Cypriot units of measurement, Cypriot * Danish unit, Danish * Dutch unit, Dutch * English unit, English * Estonian units of measurement, Estonian * Finnish unit, Finnish * French units of measurement, French (now) * Units of measurement in France before the French Revolution, French (to 1795) * German unit, German * Greek units of measurement, Greek * Hungarian units of measurement, Hungary * Icelandic units of measurement, Icelandic *Old Irish units of measurement, Irish * Italian units of measurement, Italian * Latvian units of measurement, Latvian * Luxembourgian units of measurement, Luxembourgian * Maltese units of measurement, Maltese * Norwegian units of measure, Norwegian * Old Polish units of measurement, Polish * Portuguese customary units, Portuguese * Ancient Roman weights and measures, Roman * Romanian units of measurement, Romanian * Obsolete Russian weights and measures, Russian * Obsolete Scottish units of measurement, Scottish * Serbian units of measurement, Serbian * Slovak units of measurement, Slovak * Spanish customary units, Spanish * Swedish unit, Swedish * Swiss units of measurement, Switzerland * Ottoman units of measurement, Turkish * Obsolete Tatar weights and measures, Tatar * Welsh units of measurement, Welsh

North America

* Costa Rican units of measurement, Costa Rican * Cuban units of measurement, Cuban * Haitian units of measurement, Haitian * Honduran units of measurement, Honduran * Mexican units of measurement, Mexico * Nicaraguan unit of measurement, Nicaraguan *Puerto Rican units of measurement, Puerto Rican

South America

*Argentine units of measurement, Argentine *Bolivian units of measurement, Bolivian *Brazilian units of measurement, Brazilian *Chilean units of measurement, Chilean *Colombian units of measurement, Colombian *Paraguayan units of measurement, Paraguayan *Peruvian units of measurement, Peruvian *Uruguayan units of measurement, Uruguayan *Venezuelan units of measurement, Venezuelan

Ancient

*Ancient Arabic units of measurement, Arabic *Biblical and Talmudic units of measurement, Biblical and Talmudic *Ancient Egyptian units of measurement, Egyptian *Ancient Greek units of measurement, Greek *Hindu units of time, Hindu *History of measurement systems in India, Indian *Ancient Mesopotamian units of measurement, Mesopotamian *Persian units of measurement, Persian *Ancient Roman units of measurement, Roman

Notes and references

Bibliography

* Tavernor, Robert (2007), ''Smoot's Ear: The Measure of Humanity'',

External links

CLDR - Unicode localization of currency, date, time, numbersA Dictionary of Units of Measurement
*Reasonover's Land Measure

*[https://web.archive.org/web/20060226162744/http://aurora.regenstrief.org/~schadow/units/UCUM/ucum.html The Unified Code for Units of Measure] {{SI units Systems of units, * Measurement Conceptual systems

History

Current practice

Metric system

Imperial and US customary units

Natural units

Non-standard units

Area

Energy

Units of currency

Historical systems of measurement

Africa

Asia

Europe

North America

South America

Ancient

See also

Notes and references

Bibliography

External links