The mile is a unit of length in the metric system, equal to 1.60931 kilometers. It is also the basic distance unit used throughout the United States of America and many countries of the world. The word “mile” comes from the Latin word for “a thousand paces,” although its actual origins are still debated by scholars. The Romans used it to measure distances from one water source or naval station to another. Over time, other units were also derived from the mile, including the yard, league, foot and inch. Today, various definitions of the mile exist, but it is most commonly defined as 3,280 feet or 1.609 kilometers.

The inch is a commonly used length unit in the United States and many other countries. An inch is equal to 0.00039 meters. The inch was originally a Roman unit of length, equal to 1/12 of a foot. It became an SI unit in the early 19th century, and is now one of the six standard lengths interdependent with meters (along with meter, kilometer, millimeter, micro meter, and nano meter). In 1935, theUSEb added the “point” to the name of the inch; thus 0.0003936 meters becomes 3.62 points, or 1/32nd of an inch.