Mean Sea Level (MSL) is the average height of the ocean's surface, measured over a long period, typically 19 years. It serves as a reference point for determining elevations and depths on land and in water. MSL is influenced by various factors, including tides, atmospheric pressure, and ocean currents. MSL is crucial for navigation, mapping, and construction projects. It helps in understanding sea level rise, which is linked to climate change and melting ice caps. Accurate measurements of MSL are essential for coastal management and protecting ecosystems, as well as human settlements near the coast.