The Super Nintendo introduced new features, particularly with its controllers. Unlike the NES, which had A/B/Select/Start and a d-pad, the Super Nintendo added X/Y buttons, a design that remains with Nintendo today.
Many gamers question why Nintendo chose A/B/X/Y instead of A/B/C/D. An old issue of Nintendo Power addressed this query, providing insight into the decision.
The A/B/X/Y layout was linked to the use of CAD software, where A/B are primary buttons and X/Y are secondary. Nintendo applied this CAD approach to the SNES controller design.
“Turns out the A/B/X/Y decision was tied to the use of CAD software.”
— Nintendo Power
