Before the advent of built-in embroidery, sewing machines had multiple cams that would be installed to sew any number of different stitches. Each cam would give you access to a different embroidery stitch.
The Pfaff 332 came with a built-in cam system they called "Dial-A-Stitch" which meant you didn't have to carry any more cams. Just turn the appropriate knob or dial in the right combination and you had access to a multitude of embroidery stitches.
It was quite a complicated set of knob and dial positions. Pfaff devised a wheel computer that would enable the user to pick an embroidery stitch and determine the corresponding dial setting.
These Pfaff 332 and similar sewing machines always remind me of old Navy battleships, tough and unsinkable.
If you run across one of these, the most common issue is a gummed-up cam system. Old oil residue in the cam system needs to be cleaned out carefully so as not to damage the delicate cam mechanism.