Why do people put salt on ice?

Why do people put salt on ice? When added to ice, salt first dissolves in the film of liquid water that is always present on the surface, thereby lowering its freezing point below the ices temperature. Ice in contact with salty water therefore melts, creating more liquid water, which dissolves more salt, thereby causing more ice to melt, and so on.

When added to ice, salt first dissolves in the film of liquid water that is always present on the surface, thereby lowering its freezing point below the ices temperature. Ice in contact with salty water therefore melts, creating more liquid water, which dissolves more salt, thereby causing more ice to melt, and so on.