CD’s – What Are They?

CD is an acronym for Compact Disc.

CDs are made with 5 different layers…

1. A wide, pliable, and transparent plastic layer. This makes most of the CD’s width and mass. It serves as shield for the data layer (due to damage on the play side) and also as a lens to direct the CD player’s laser to the data layer to aid in data reading.

2. The data layer contains the CD’s information. It’s what the CD player “reads” to produce audio, video, and others. It is cast or pressed on top of the transparent plastic layer. Information kept in the data layer is organized into tracks that twist similar to the grooves of a vinyl record. CDs, unlike vinyl records, are read in an “inside out” manner.

3. A reflective, metallic layer is put on top of the data layer. It lets the disc serve as a mirror, reflecting the CD player’s laser to the CD player’s detector after it read the data. This makes the CD’s play-side glossy.

4. A sheer yet tough protective layer is an ultra-thin plastic covering both the reflective and data layers, and at the same time, creating a plane where to print the label information.

5. Lastly, the label layer is printed over the protective layer. It bears the CD title, band name, graphics, and other data regarding the CD’s contents.