PC Floppy
From Vogons Wiki
PC Floppy refers to the floppy drive interface in IBM compatible PCs, as distinct from the methods used for controlling floppy drives by other contemporary computers such as the Amiga.
It uses a 34-pin ribbon cable, with a twist to swap some control lines. This allows drives to be configured to listen on the same address lines, and their position (A: or B:) is controlled by whether they are installed on connectors located before or after the cable twist.