Glaciers are large masses of ice that are currently moving or previously been moving.
There are two basic types of glaciers, valley glaciers and continental glaciers, both of which are catagorized by their size and shape. A valley glacier , also called alpine glaciers, form in the high altitudes of mountain ranges where snow accumulates in valleys. These glaciers slowly make their way down the mountain toward lower elevations. The second type of glacier, the continental glacier , is much larger then a valley glacier. A continental glacier is a slow moving sheet of ice may lie over land or water.