Compare and contrast valley glaciers and ice sheets?

An ice-sheet refers to a huge mass of glacier mass that envelopes the majority of the land in the Polar regions. The ice-sheets envelope thousands of kilometers of the land surface of Earth. While valley glaciers refer to the streams of flowing ice in the mountain valleys. These glaciers enhance the depth and increase the sides of the mountain valleys with the help of abrasion.  

Ice-sheets are found at the two Polar parts of the Earth, approximately 80 percent of Greenland in the Northern Hemisphere and about 98 percent of Antarctica in the Southern Hemisphere are enveloped by ice-sheets. These two regions of ice-sheets comprise 99 percent freshwater.  

The glaciers are constrained by the surrounding topography, while the ice-sheets covers bigger regions of the Earth.