How does a dvd-rw able to be rewritten?

Question

How does a dvd-rw able to be rewritten?

Answer 1

DVD-r have a solid layer that is writeable. DVD-RW replace the solid layer with a viscous photosensitive layer that allows activation and deactivation by the laser. this viscous layer also makes DVDRW more delicate and sensitive to excess heat and direct sunligth.