The meter (m) is the base unit of length in the International System of Units, originally defined by the distance light travels in a vacuum in 1/299,792,458 of a second. It serves as the foundation for all metric length measurements and is used in construction, sports, and scientific research worldwide. One meter equals roughly 3.2808 feet or about 1.0936 yards.

The kilometer (km) equals 1,000 meters and is the standard unit for measuring long distances between cities, countries, and geographic features. Road signs in most countries display distances in kilometers, and running races commonly use kilometer markers. One kilometer is equivalent to about 0.6214 miles, making it easy to convert between metric and imperial distance scales.