What is an international nautical mile?
An international nautical mile is exactly 1,852 meters, which is about 1.15078 statute miles. The word 'nautical' distinguishes it from the statute mile used on land.
Because the nautical mile began as one minute of latitude, the Earth's circumference works out at roughly 21,600 nautical miles (360 degrees of 60 minutes each). Navigators measure distance directly off the latitude scale on a chart.
A tenth of a nautical mile is a cable, which is 185.2 meters and is still used for short distances at sea. Minutes and seconds belong to the angles of latitude and longitude, not to the unit itself.
What is a meter?
The meter is the SI base unit of length and is equal to 100 centimeters or 1,000 millimeters. It was originally defined as one ten-millionth of the distance from the North Pole to the equator along the meridian through Paris. Since 1983 it has been the distance light travels in a vacuum in 1/299,792,458 of a second.