The United States system of units of 1832 is based on the system in use in Britain prior to the introduction to the British imperial system on January 1, 1826. Both systems are derived from English units, a system which had evolved over the mille…

For measuring length, the U.S. customary system uses the inch, foot, yard, and mile, which are the only four customary length measurements in everyday use. From 1893, the foot was legally defined as exactly 1200⁄3937 m (approximately 0.304…