One nautical mile is defined by one latitude minute of arc (there are 60 such minutes to a degree). This equals 1852 meters, and roughly (but coincidentally) 2000 yards or 6000 feet. (Edit: actually, a standard nautical mile is 6076 feet, 6000 feet and 2000 yards are commonly used approximations, but produce an error of about 1%).

The statute mile had a little fuzzier definition to start with, as one mile was the same as 1000 roman PAces/steps. The definition has since changed, but one statute mile equals about 1609 meters.