Mars hydrology is the study of water on Mars, including its distribution, movement, and interactions with the Martian surface and atmosphere. This field of research focuses on understanding the history of water on Mars, including ancient lakes, rivers, and oceans, as well as the potential presence of subsurface water ice and liquid water in the present day. Scientists study the role of water in shaping the Martian landscape, as well as its potential implications for the possibility of past or present life on the Red Planet. The search for water on Mars is a key aspect of current Mars exploration missions and is important for understanding the planet's past, present, and future habitability.