Maps supports several distance units which you can use in all the functionality added by it, and it's extensions.
Unit (in metres): supported notations
- Meters (1m): m, meter, meters
- Kilometres (1000m): km, kilometers, kilometres
- Miles (1609.344m): mi, mile, miles
- Nautical miles (1852m): nm, nautical mile, nautical miles
At the moment there is no way to convert distances to use another unit yet. This will be added in the future though.