Turning is optional, and you get to choose to turn left or turn right. Turning happens after a move, therefore a piece may not turn without moving. Some other games have an element of turning, but neither as free nor as generalized as in Turning Chess.
Pawns turn, too.
For example 1. This is permitted, but you will very rarely want to do it. If you use the FIDE army, only Pawns, Rooks, and Bishops are affected by turning. I believe it would be much more interesting to use any of the armies from Chess with Different Armies, or to use the Amontillado Army . The Fibnif, for example, produces four different movement patterns as it turns.