Sure in a nutshell a sequential switch let’s you split a signal and route it to different paths sort of like cv mixer but not quite. Chris Meyer of Learning Modular explains it better than my feeble fumbling:
This module comes in a few different forms; in the most common, a few different inputs are routed to one output (although they are usually symmetrical – one input can be switched between several outputs). A pulse or gate input then steps through the inputs one at a time, switching which ones is routed to the output. Fancier sequential switches allow you to set the number of stages, to divide an input clock so it switches at a slower tempo than the master clock, or might directly route a series of inputs to corresponding outputs (with usually a summed output as well).
https://learningmodular.com/glossary/sequential-switch/
It’s a great modular utility along with cv mixer, matrix mixers, attenuators, VCA and logic modules to make interesting patches.