Do you mean the front-to-back sliding and locking of the "adjustable" steering wheel on the steering shaft column or something else ?
If that is it, the back of the steering wheel hub has a collet with fingers that are internally splined and externally threaded. Around the fingers is a threaded clamping ring that closes the gaps between the fingers as the threads are "tightened".
The steering wheel and collet slide to and fro on an externally splined steering shaft.
When a comfortable steering wheel position (if there is one) is reached, the clamping ring is threaded "tighter" and the splined fingers firmly grasp the splined steering shaft.
If it's something esle.... I don't know.