Meters above sea level

Meters Above Sea Level (MASL) is a standard metric measurement of the elevation of a location in reference to mean sea level.

Uses
Meters above sea level is the standard measurement of the elevation or altitude of:
 * a geographic location such as a town, mountain, or other landmark
 * the elevation of the top of a building or other structure
 * or the altitude of an airplane or other flying object.

How determined
The elevation or altitude in Meters above sea level of any location, object, or point, can be determined in a number of ways. The most common include:
 * Global Positioning System (GPS) which triangulates its location in reference to multiple satellites
 * an altimeter, which typically measures atmospheric pressure, which decreases as altitude increases.
 * a topographic map or digital elevation model map, for which elevations have been determined by aerial photography or geologic surveys.

Other measurement systems
Feet above sea level is the most common analogue for meters above sea level in the American measurement system.

Abbreviations
Meters above sea level is sometimes abbreviated as m.a.s.l. or m.s.l.