Here's how it works:

* Meltwater: As glaciers move, meltwater seeps into cracks and crevices in the bedrock.

* Freezing: The water freezes and expands, putting pressure on the rock.

* Plucking: The ice then pulls away pieces of the rock, essentially "plucking" them from the bedrock.

These plucked rocks are then transported by the glacier and eventually deposited elsewhere, often forming glacial deposits like moraines.