Orientation

From Speedsolving.com Wiki

Orientation refers to the way a piece is flipped or rotated. On the 3x3x3 Rubik's cube, corners and edges each have their own orientation; corners can be oriented 3 different ways, and edges can be oriented in 2 different ways. On a Super Cube or Picture Cube, the centers can also be oriented (resulting in extra work to solve), but this is not the case on standard cubes. Because of how the cube behaves, only pairs of like pieces can be oriented; it is impossible to orient just one piece. If you rotate one corner clockwise, another must be rotated counterclockwise.

Oriented edges can be solved with R, U, L, and D moves, while oriented corner can be solved with U and D moves.

See also