A backdash is a backwards step performed with two back-directional inputs (notation b,b). It allows a character to quickly retreat whilst blocking high and middle attacks.
Techniques
Backdash Cancelling
Backdash Cancelling, also known as Korean Backdash is a movement technique used to quickly retreat from the opponent by backdashing multiple times in quick succession. It involves performing a backdash, cancelling its recovery with a crouch (notation d/b), and following with another backdash.