The single pole double throw switch (SPDT) is commonly referred to as a “3-way switch” as in your home. It is very simple to wire if you know this tiny little secret:

The common on the switch is often black. The other two are either brass or silver. Secret: on one switch common is power and on the other switch it goes to your light. The other two connections are called "travelers" and connect the two switches together and don't care how.

Common uses:

One switch upstairs & one downstairs both control one light or group of lights.

One switch at each end of a hallway but control the same hallway light(s)

One switch leading to a garage and another in the garage.