A flag is a piece of

fabric Textile is an umbrella term that includes various fiber-based materials, including fibers, yarns, filaments, threads, different fabric types, etc. At first, the word "textiles" only referred to woven fabrics. However, weaving is not the ...

(most often rectangular or

quadrilateral In geometry a quadrilateral is a four-sided polygon, having four edges (sides) and four corners (vertices). The word is derived from the Latin words ''quadri'', a variant of four, and ''latus'', meaning "side". It is also called a tetragon, ...

) with a distinctive design and colours. It is used as a

symbol A symbol is a mark, sign, or word that indicates, signifies, or is understood as representing an idea, object, or relationship. Symbols allow people to go beyond what is known or seen by creating linkages between otherwise very different conc ...

, a

signalling In signal processing, a signal is a function that conveys information about a phenomenon. Any quantity that can vary over space or time can be used as a signal to share messages between observers. The ''IEEE Transactions on Signal Processing'' ...

device, or for decoration. The term ''flag'' is also used to refer to the

graphic design Graphic design is a profession, academic discipline and applied art whose activity consists in projecting visual communications intended to transmit specific messages to social groups, with specific objectives. Graphic design is an interdiscipli ...

employed, and flags have evolved into a general tool for rudimentary signalling and identification, especially in environments where communication is challenging (such as the maritime environment, where

semaphore Semaphore (; ) is the use of an apparatus to create a visual signal transmitted over distance. A semaphore can be performed with devices including: fire, lights, flags, sunlight, and moving arms. Semaphores can be used for telegraphy when arra ...

is used). Many flags fall into groups of similar designs called

flag families Flag families are sets of national flags with similarities in their design, often based on a shared history, culture, or influence. Families do not include flags with coincidental similarities. Flags may be in multiple flag families. Only twelve c ...

. The study of flags is known as "

vexillology Vexillology ( ) is the study of the history, symbolism and usage of flags or, by extension, any interest in flags in general.Smith, Whitney. ''Flags Through the Ages and Across the World'' New York: McGraw-Hill, 1975. Print. The word is a synthe ...

" from the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

, meaning "flag" or "

banner A banner can be a flag or another piece of cloth bearing a symbol, logo, slogan or another message. A flag whose design is the same as the shield in a coat of arms (but usually in a square or rectangular shape) is called a banner of arms. Also, ...

National flag A national flag is a flag that represents and symbolizes a given nation. It is flown by the government of that nation, but usually can also be flown by its citizens. A national flag is typically designed with specific meanings for its colours ...

s are

patriotic Patriotism is the feeling of love, devotion, and sense of attachment to one's country. This attachment can be a combination of many different feelings, language relating to one's own homeland, including ethnic, cultural, political or histor ...

symbols with widely varied interpretations that often include strong

military A military, also known collectively as armed forces, is a heavily armed, highly organized force primarily intended for warfare. It is typically authorized and maintained by a sovereign state, with its members identifiable by their distinct ...

associations because of their original and ongoing use for that purpose. Flags are also used in

messaging A message is a discrete unit of communication intended by the source for consumption by some recipient or group of recipients. A message may be delivered by various means, including courier, telegraphy, carrier pigeon and electronic bus. A ...

advertising Advertising is the practice and techniques employed to bring attention to a product or service. Advertising aims to put a product or service in the spotlight in hopes of drawing it attention from consumers. It is typically used to promote a ...

, or for

decorative Beauty is commonly described as a feature of objects that makes these objects pleasurable to perceive. Such objects include landscapes, sunsets, humans and works of art. Beauty, together with art and taste, is the main subject of aesthetics, o ...

purposes. Some military units are called "flags" after their use of flags. A ''flag'' (Arabic: ) is equivalent to a

brigade A brigade is a major tactical military formation that typically comprises three to six battalions plus supporting elements. It is roughly equivalent to an enlarged or reinforced regiment. Two or more brigades may constitute a division. Br ...

in Arab countries. In Spain, a ''flag'' (Spanish: ') is a

battalion A battalion is a military unit, typically consisting of 300 to 1,200 soldiers commanded by a lieutenant colonel, and subdivided into a number of companies (usually each commanded by a major or a captain). In some countries, battalions are ...

-equivalent in the

Spanish Legion For centuries, Spain recruited foreign soldiers to its army, forming the Foreign Regiments () - such as the Regiment of Hibernia (formed in 1709 from Irishmen who fled their own country in the wake of the Flight of the Earls and the penal ...

History

The origin of the flag is unknown and it remains unclear when the first flag was raised.Flags through the ages and across the world : Smith, Whitney page 33
/ref> Ships with vexilloids were represented on predynastic Egyptian pottery . In antiquity,

field sign {{Distinguish, field mark A field sign is an unofficial differencing mark worn on a combatant's clothing to show the difference between friend and foe or a combatant and a civilian. Examples *A tabard in the livery colors of a lord and bearing hi ...

s or standards that can be categorised as

vexilloid A vexilloid is any flag-like (vexillary) object used by countries, organisations, or individuals as a form of representation other than flags. American vexillologist Whitney Smith coined the term ''vexilloid'' in 1958, defining it as This in ...

or "flag-like" were used in warfare, which originated in ancient Egypt or

Assyria Assyria (Neo-Assyrian cuneiform: , romanized: ''māt Aššur''; syc, ܐܬܘܪ, ʾāthor) was a major ancient Mesopotamian civilization which existed as a city-state at times controlling regional territories in the indigenous lands of the A ...

.Flag , heraldry
''Encyclopedia Britannica''. Retrieved February 15, 2019. Examples include the

Sassanid The Sasanian () or Sassanid Empire, officially known as the Empire of Iranians (, ) and also referred to by historians as the Neo-Persian Empire, was the last Iranian empire before the early Muslim conquests of the 7th-8th centuries AD. Named ...

battle standard

Derafsh Kaviani Derafsh Kaviani ( fa, درفش کاویانی) was the legendary royal standard Derafsh (in Latin: vexilloid) of Iran (Persia) used since ancient times until the fall of the Sasanian Empire. The banner was also sometimes called the "Standard of J ...

, and the standards of the

Roman legion The Roman legion ( la, legiō, ) was the largest military unit of the Roman army, composed of 5,200 infantry and 300 equites (cavalry) in the period of the Roman Republic (509 BC–27 BC) and of 5,600 infantry and 200 auxilia in the period of ...

s such as the

eagle Eagle is the common name for many large birds of prey of the family Accipitridae. Eagles belong to several groups of genera, some of which are closely related. Most of the 68 species of eagle are from Eurasia and Africa. Outside this area, just ...

Augustus Caesar Caesar Augustus (born Gaius Octavius; 23 September 63 BC – 19 August AD 14), also known as Octavian, was the first Roman emperor; he reigned from 27 BC until his death in AD 14. He is known for being the founder of the Roman Pri ...

's Xth legion and the dragon standard of the

Sarmatians The Sarmatians (; grc, Σαρμαται, Sarmatai; Latin: ) were a large confederation of Ancient Iranian peoples, ancient Eastern Iranian languages, Eastern Iranian peoples, Iranian Eurasian nomads, equestrian nomadic peoples of classical ant ...

; the latter was allowed to fly freely in the wind, carried by a horseman, but depictions suggest that it bore more similarity to an elongated

dragon kite Kites are tethered flying objects which fly by using aerodynamic lift, requiring wind (or towing) for generation of airflow over the lifting surfaces. Various types of kites exist, depending on features such as material, shape, use, or operatin ...

than to a simple flag. While the origin of the flag remains a mystery, the oldest flag discovered is actually made of bronze and is called a

Derafsh The Derafsh ( fa, درفش) was a flag-like object used as a military standard by units in the Ancient Iranian (Persian) army. History Derafsh refers to a piece of skin or cloth, usually with different patterns and colors, which is used as on ...

or 'flag-like' Shahdad, which was found in

Shahdad Shahdad ( fa, شهداد, also Romanized as Shahdād; formerly, Khabīs) is a city and capital of Shahdad District, in Kerman County, Kerman Province, Iran. At the 2006 census, its population was 4,097, in 1,010 families. District Shahdad is t ...

, Iran, and dates back to c. 2400 BCE. It features a seated man and a kneeling woman facing each other, with a star in between. This iconography can be found in other Bronze Age pieces of art in the area as well. Flags as recognized today, made of a piece of cloth representing a particular entity, were almost certainly the invention of the ancient peoples of the

Indian subcontinent The Indian subcontinent is a list of the physiographic regions of the world, physiographical region in United Nations geoscheme for Asia#Southern Asia, Southern Asia. It is situated on the Indian Plate, projecting southwards into the Indian O ...

or the

Zhou dynasty The Zhou dynasty ( ; Old Chinese ( B&S): *''tiw'') was a royal dynasty of China that followed the Shang dynasty. Having lasted 789 years, the Zhou dynasty was the longest dynastic regime in Chinese history. The military control of China by th ...

Ancient China The earliest known written records of the history of China date from as early as 1250 BC, from the Shang dynasty (c. 1600–1046 BC), during the reign of king Wu Ding. Ancient historical texts such as the '' Book of Documents'' (early chapte ...

. Chinese flags had devices such as a red bird, a white tiger, or a blue dragon, and royal flags were to be treated with a level of respect similar to that given to the ruler. Indian flags were often triangular and decorated with attachments such as a

yak The domestic yak (''Bos grunniens''), also known as the Tartary ox, grunting ox or hairy cattle, is a species of long-haired domesticated cattle found throughout the Himalayan region of the Indian subcontinent, the Tibetan Plateau, Kachin Sta ...

's tail and the state umbrella. Silk flags spread to the Near East from China or it was simply the

silk Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the coc ...

which made the journey to be fashioned by people who had independently arrived at the idea of rectangle clothed attached to a pole. Flags were probably transmitted to Europe via the

Muslim world The terms Muslim world and Islamic world commonly refer to the Islamic community, which is also known as the Ummah. This consists of all those who adhere to the religious beliefs and laws of Islam or to societies in which Islam is practiced. I ...

, where plainly coloured flags were being used due to Islamic proscriptions. They are often mentioned in the early history of Islam and may have been copied from India. In Europe, during the

High Middle Ages The High Middle Ages, or High Medieval Period, was the periodization, period of European history that lasted from AD 1000 to 1300. The High Middle Ages were preceded by the Early Middle Ages and