The tape recorder makes use of mangnetic tapes which are thin, plastic ribbons a quarter of an inch wide. One side is dull and this is coated with a magnetic slide of iron on which the recording is made.
Recorders produced since 1959 have halved the tracks once more and the tape is thus used for four tracks. This has meant that the playing time has quadrupled, but with such narrow tracks particles of dust will lift the head away from the tape and cause distortion of sound; hence it is essential to keep tapes free of dust.