Types:
 

Cirque glacier: a glacier that has carved a cirque and is wholly contained within the cirque.
 

Cirque: an amphitheatre-shaped depression scoured by a glacier into the side of a mountain.

Horn: A mountain peak between 2 or more cirques. Example: The Matterhorn

Arete: A knife-edge ridge between two cirques, usually connecting 2 horns.

Tarn: a lake occupying a cirque.

Alpine or valley glacier: a glacier originating in a cirque or high altitude snow field that flows within a pre-existing valley. Glacial erosion greatly modifies the valley into a characteristic U-shaped valley.
 

Piedmont glacier: A glacier formed by the coalescing of valley glaciers that flowed onto the

pediment, a flat low-lying erosional surface at the foot of a mountain range.

Piedmont glaciers were important in forming ice sheets in the U.S. western interior during the Pleistocene (epoch of geologic time of the most recent ice ages).
 

Ice Sheet: A thick, extensive body of glacial ice that is not confined to valleys. Ice sheets cover an area 10⁶ to 10⁷ square kilometers. Ice flow is radial from the centers of ice domes that merge to form an ice divide. Modern examples include Greenland and the East and West Antarctic Ice Sheets of Antarctica.
 

Ice Cap: A thick, extensive body of glacial ice that is not confined to valleys. Ice caps cover an area 10² to 10⁴ square kilometers. Ice flow is radial from the center of 1 or more ice domes that may merge to form an ice divide. Modern examples include the Barnes and Penny Ice Caps on Baffin Island, ice caps on Spitsbergen, and Vatnajokull, Hofsjokull, Langjokull, and
Myrdalsjokull ice caps on Iceland.
 

Ice Shelf: a floating glacier derived from a land based ice sheet. An ice shelf is thick enough to have internal flow, but is over water. Modern examples include the Ross and Ronne/Filchner Ice shelves in Antarctica.

C.f. Pack Ice = frozen seawater that is not a glacier, but seasonally covers most of the Arctic ocean, and large portions of the South Atlantic, South Pacific, and Southern Indian oceans surrounding the continent of Antarctica.

Outlet glacier: a segment of a continental glacier (ice cap or ice sheet) that advances rapidly through a mountain pass.
 

Ice Stream: A linear zone within an ice sheet, measured in 10's of kilometers across and 100's of kilometers in length, that is flowing significantly faster than the surrounding ice.