What are relays? You need relays for various DC/AC devices. Even your car has 30-40 relays on it for your head lamps, tail lights, turn signals, and etc…
Here’s an example of making a Party Light using a CUSB22R that has relays on-board.
You have couple options:
For higher voltage applications, you might want to try:
Allen Bradley relays
Mouser catalog has good options for relay searching too.