Well, the important thing about CD is in fact lasers. It was first introduced in 1960 but didn't have any applications. But, back to CD's. These were introduced in 1980 and have gradually replaced vinyl records for use in home stereo systems.
CDs can also store lots of information.
Instead of grooves as on a record, a CD has a track of tiny pits in a silvery reflective layer on a plastic disc. This layer is protected by a tough plastic coating to prevent damage from dust or scratches. Unlike a vinyl record the tracks are read from the centre outwards. Although CDs have only one recording side they can hold over an hour of music. When a CD is played, a tiny laser beam from inside the player moves across the disc.