How does ripping a CD/DVD work exactly? Is it similar to copying or does it leave the CD/DVD unusable?

I've never ripped CDs or DVDs before for any reason and am curious how this works since I have some stuff I wanna see about backing up but am nervous about ruining the disc. I've tried looking this up, but every time I do, I obviously am searching for the wrong thing because I have never found the info I'm looking for.