system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How burning data to a disc works.

And what makes CD-RWs capable of being rewritten while CD-Rs aren't.
gpt
The CD has little beads of a chemical that react to the laser.  If the laser zaps a bead, it changes the reflective property.  So the drive can write 0s and 1s by zapping or not zapping each bead.  (one bead is one bit).  Then when it goes to read them, it can tell by the reflection whether it's 0 or 1.

CDRW has chemicals that can be zapped a second time to reset them.