You may have heard of a glacier. You know, the big hulking ice pack that looms and lurks throughout the colder regions of the planet? They're pretty famous for their whole melting crisis right now. Yet you might not know exactly how influential glaciers have been throughout geologic history is forming our landscapes.
There are three distinct ways that glaciers shape the land: 1) erosion 2) transportation and 3) deposition. Erosion picks up material through weathering through plucking and abrasion. That material is then transported as it moves downhill. Sometimes the material is hidden inside or at the base of the glacier, or sometimes it is on top of the glacier, accounting for the dirty color of some glaciers. Those rocks and other transported materials eventually get deposited to a new place as the glacier melts; this leftover material is called glacial till, and it's what forms many of our landscapes today from the last ice age!