From Sonic Retro
The Quick Step is a move used in Sonic Unleashed, Sonic Colours, Sonic Generations, and Sonic Forces. As the name suggests, it allows Sonic the Hedgehog to quickly move to his left or right while running. The Quick Step is used primarily to avoid oncoming obstacles, such as spikes, or to move to another runway to avoid falling to an unpleasant death; for example, crossing the piers at the start of Jungle Joyride's Act 1. In Colours, the move is only usable in certain sections, while in the other titles it is usable anytime.