In 1927, a Russian immigrant to Britain, Boris Rtcheouloff had applied for a patent based on Valdemar Poulsen's invention describing an apparatus for recording pictures and sound on a travelling metallic wire.
During the early 1950's the recording of pictures and sound was a very restritcted process used only for professional applications, as known as VTR or Video Tape Recorder.
In the reality, the VTR had many advantages when compared with earlier similar recording process, as it allows that the video and sound signals could be recorded simultaneously without any previous technical arrangements to obtein for instance, the sound tracks like in the movie-pictures.
Furthermore in spite of its simple operation, the recorded tape has a reduced demage rate during the playback mode and in this way it can be used for many times easily.
Due to the continuous improvement in the chemical formulation of the recording media used in the new magetic tapes as well as in the desing of the new recording heads, the electronic industry launched in the world market the first home video recording systems, such as the U-MATIC, invented by Sony Corporation in Japan. (a)
In the mid 1970's there were available four commercial home video recording systems as per indicated in table (b).

(*) As known as VHS or Video Home System

Table 5: Showing diverse systems recording and video signals reproduction for domestic applications in the middles of the decade of 1970.

However, due to several circunstances only the VHS system stayed in the market consolidating the VCR or videocassette recorder.
It is interesting to note that simultaneously to the development of the recording of the pictures and sound signals on magnetic tape, engineers were working also in differents processes giving birth of the videodisc.
In this way, in 1972, Philips demonstrated the first practical long-playing videodisc technically far superior when compared with its forerunner launched in 1970 by the joint venture TELDEC (AEGTelefunke/Decca).
In theTELDEC sytem the pictures and sound signals were still recorded in grooves using a mechanical tracking and so it had a very low playback time up to 5 minutes. By other hand the Philips system used an advanced concept of sub-microscopic dots arranged in a spiral track whose reading was done by mean of coherent light or - Laser - allowing a playback time around 30 to 40 minutes. (a)

		(d) Modern videocassette recorder using the VHS sytem made by Panasonic. (Courtesy of Panasonic do Brasil)
(a) Recording head used in a modern home video recorder.	(a) Pictorial aspects of the evolution of the video tape recorders: (a) Video tape recorder using the U-MATIC system launched in the market circa 1971. (b) Forrunner of the model VCR using the BETAMAX system. (c) First solid state VTR circa 1964.