In 1935, years before the introduction of the Compact Cassette, AEG, released the first reel-to-reel tape recorder (in German: Tonbandgerät), with the commercial name "Magnetophon", based on the invention of the magnetic tape (1928) by Fritz Pfleumer, which was using similar technology, but with open reels, for which the tape was manufactured by BASF. These instruments were still very expensive and relatively difficult to use, therefore were mostly used by professionals in Radio Stations and Sound Studios. For private use the (reel to reel) tape recorder was not very common and only slowly took off from about the 1950s. With prices between 700 and 1500 DM (which would now be about 3100 to 6700 EUR) still being far too expensive for the mass market and while still using vacuum tubes built very bulky. In the 1960s however the prices dropped, so that Reel-to-Reel Tape Recorders could have been found in the better equipped households from then on.
In 1958, following four years of development, RCA Victor introduced the stereo, quarter-inch, reversible, reel-to-reel RCA tape cartridge. It was a cassette, big (5" x 7"), but offered few pre-recorded tapes; despite multiple versions, it failed.
In 1962 Philips invented the compact audio cassette medium for audio storage, introducing it in Europe in August, 1963 (at the Berlin Radio Show), and in the United States (under theNorelco brand) in November 1964, with the trademark name Compact Cassette.
Although there were other magnetic tape cartridge systems, the Compact Cassette became dominant as a result of Philips' decision in the face of pressure from Sony to license the format free of charge. Philips also released the Norelco Carry-Corder 150 recorder/player in the U.S. in November 1964. By 1966 over 250,000 recorders had been sold in the US alone and Japan soon became the major source of recorders. By 1968, 85 manufacturers had sold over 2.4 million players