Do the DVD and the CD store information through optic technology??

Question

Do the DVD and the CD store information through optic technology??

Answer 1

Yes. Pressed DVDs and CDs have little pits in a metal layer between plastic, self-burned DVDs and CDs have a layer of dye that gets burned dark by the laser. In both cases, the reflectivity is changed, depending on whether there is a pit/burned dark or not.