This article presents information on the method of magnetic tape recording. Apart from audio recording, magnetic tape has also found wide application in analog video recording, as well as digital data recording. The base film in a magnetic tape is typically made of polyethyleneterephtalate, with a thickness down to 7 mm. If a thinner base film is required, materials with a higher Young's modulus, such as polyethylene-2,6-naphthalate, have to be used. High-density recording is only possible if the magnetic surface is very smooth, which, in turn, presupposes a smooth base film. Maghemite is the light-brown material found on open-reel computer tapes, studio audiotape, and International Electrotechnical Commission's audiocassettes.