: an isomer that is a stereoisomer of a compound having two or more chiral centers and that is not a mirror image of another stereoisomer of the same compound â
A compact disc is a deceptively simple looking device considering the technology required to make it. 1  CDs consist of three layers of materials: 2  A base layer made of a polycarbonate plastic. 3  A thin layer of aluminum coating over the polycarbonate plastic. 4  A clear protective acrylic coating over the aluminum layer.
CD ROMs, which are computer disk drives for computers, were first made in the year 1985. Writable or recordable CDs came later, in 1988. These, with the help of CD recording devices, let users make their own CDs, which they could then play on CD players. On a not so promising note, CD players are fast losing out on popularity, thanks to new digital innovations like the MP3 player.