Using any pen or marker on the disk can damage the reflective layer by crushing the data. Another problem arises because the ink may leach through the coating and attack the internal layers. The laser s light is dispersed by about eight trillion pits on the disc in a spiral track that is some 3.5 miles long. The CD will require about 22,000 revolutions to complete the journey. CD-DA transfers data at a constant 150,000 bytes per second.
Data starts at the center of the disc.
Compare this to a hard disk drive which spins at a fixed r.p.m. Every computer should have a Multi-Read compatible one. As fast as they sound, 12x drives are all but extinct. A single-speed 15x drive will run at 15x for the entire disk. At 1x, a drive can create a disc in about 80 minutes.