Foot
Symbol: ft
Using feet as measuring unit has been done early in the history of humanity.
Different humans means different sizes of feet and so there was allways a big variety in the meaning "foot".
Effective July 1, 1959 the length of the international yard in the United States and countries of the Commonwealth of Nations was defined as 0.9144 meters. Consequently, the international foot is defined to be equal to 0.3048 meters (equivalent to 304.8 millimeters). This was 2 ppm shorter than the previous U.S definition and 1.7 ppm longer than the previous British definition.
1ft = 0.3048m
1m = 3.2808ft