The word "chariot" comes from the Latin carrus, itself a loanword from Gaulish. A chariot of war or one used in military parades was called a car. In ancient Rome and some other ancient Mediterranean civilizations a biga required two horses, a triga three, and a quadriga four.
Ox carts, proto-chariots, were built by the Proto-Indo-Europeans and in Mesopotamia as early as 3000 BC. The original horse chariot was a fast, light, open, two-wheeled conveyance drawn by two or more horses that were hitched side by side, and was little more than a floor with a waist-high semicircular guard at the front. It was initially used for ancient warfare during the Bronze and the Iron Ages, but after its military capabilities had been superseded by other vehicles, the chariot was used for travel, in processions, for games, and in races.
The critical invention that allowed the construction of light, horse-drawn chariots was the spoked wheel. The earliest spoke-wheeled chariots date to ca. 2000 BC and their use peaked around 1300 BC (see Battle of Kadesh). Chariots had lost their military importance by the 1st century AD, but chariot races continued to be popular in Constantinople until the 6th century.