Unit Converters

History

The kilometer has been in use since the adoption of the metric system in the 1790s. The prefix 'kilo' comes from the Greek word 'chilioi,' meaning thousand. Most countries use kilometers for road signs and geographic distances, with the notable exceptions of the United States, United Kingdom, and Myanmar.

History

The nautical mile is based on the circumference of the Earth. Originally defined as one minute of arc along a meridian, it was standardized by the International Hydrographic Organization in 1929 at exactly 1,852 meters. It remains essential for navigation because of its direct relationship to latitude and longitude.