Streamlined glacial landforms (such as whale-backs, drumlins, and roches moutonnees) are elongated, smoothly tapered features shaped by the flow of overriding glacial ice into an aerodynamic, teardrop-like form aligned with the direction of ice movement, whereas ground moraine is simply an extensive, generally unsorted blanket of till deposited beneath a glacier across the landscape, without the smooth, elongated, flow-aligned form characteristic of streamlined landforms.