Does switch open and close an electrical unit?

Yes.

A switch can change the flow of an electrical circuit. The word switch itself means electrical power. It can also be referred to as a gate, which is used in mathematical terms.

An example of a switch is something many uses all the time, which is a computer. In a computer, there are a lot of switches, which are logical gates allowing the machine to operate and perform basic functions.

There are many types of switches, like a DIP switch, which is small and includes several switches. Other examples include surface mount switch and reed switch.