What is Quad chess?

Hello, everyone, I keep seeing references to "Rapid Quad" tournaments. I think I understand the Rapid part, but what is "Quad"?

Thanks in advance for any advice.

I believe it refers to groups of 4 (Quad) players. In the Quad, you end up playing every different opponent once (or sometimes twice, one with each color based on the format). 

If you are "A" hypothetically, then you'll play opponent B in round 1; opponent C in round 2 and opponent D in round 3.

Oh, thanks. It's not as weird as I imagined, not so different from a Swiss, I guess. I had imagined it was one of those things with a strange board and multiple people playing at once.

xD Nope, just regular chess