Corner Orientation
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Corner Orientation, abbrevaited CO, the orientation of a cube's corners. There are three possible corner cubie orientations. CO is a sub step in many methods.
For the last layer of the 3x3x3 cube there are three main variations used for the seven cases of CO, one that is named 'pure CO' wich orients the corners without affecting anything else, not even corner permutation, one preserves edge orientation wich is OLL with edges correctly oriented and the last variation orients the corners ignoring edges.
See also:
 Orientation
 Orient
 Permutation
 Edge Orientation
 Corner Permutation
 OCLL
 Winter Variation
 CLS
 Partial Corner Control
Pure CO
All cases here have long algorithms, the H case is actually the worst LL case of them all and the pi cases is second worst.
Two corners unoriented
U

T
 
L

Three corners unoriented
S

S

Four corners unoriented
H

pi
