A flag is a piece of cloth, often flown from a pole or mast, generally used for signalling or identification. The design of a flag displayed in another form is also referred to as a flag. The first flags were used to assist military coordination on battlefields, and flags have evolved into a general tool for rudimentary signalling and identification, especially in environments where communication is similarly challenging (such as the maritime environment where semaphore is used). National flags are potent patriotic symbols with varied wide-ranging interpretations, often including strong military associations due to their original and ongoing military uses. Flags are used in messaging or advertising, or for decorative purposes, though at this less formal end the distinction between a flag and a simple cloth banner is blurred. The study of flags is known as vexillology, from the Latin vexillum meaning flag or banner.

History

Although flag-like symbols have been used by ancient cultures for thousands of years, the origin of flags in the modern sense is a matter of dispute. Some believe flags originated in China, while others hold that the Roman Empire's vexillum was the first true flag. Originally, the standards of the Roman legions were not flags, but symbols like the eagle of Augustus Caesar's Xth legion; this eagle would be placed on a staff for the standard-bearer to hold up during battle. But a military unit from Scythia had for a standard a dragon with a flexible tail which would move in the wind; the legions copied this; eventually all the legions had flexible standards — our modern-day flag.