The foot is the basic unit of length in the metric system and is equal to 3.2808 meters. It’s also the primary unit of linear measure in customary systems of measurement, including the English system. The foot is defined as the length of a line from the heel of one person to the toe of another person, with each foot positioned at the same level. Originally, a foot was defined as being equal to 12 inches, but this definition was later changed to its current value.

The yard is the traditional length unit of linear measure. It is traditionally equivalent to 0.9144 meters, though it has been varied between 9 and 12 feet in recent times. The yard was first conceptualized by fifth-century BC Egyptians and was standardized as 9 feet in 1795 by the French military engineer General Hoche. During the American Revolutionary War, the Continental Army was unimpressed with various proposals for a new foot measuring system and instead adopted the British yard as their standard. The use of the yard spread rapidly throughout the world after that due to its international compatibility. Today, most countries use either the metric system or a variant of it, and there are few remaining areas where yards are used; Africa mostly uses meters, India uses centimeters, parts of Asia use traditional units like li and fen.