parent nodes: Robotech | vhs
The Video Home System, better known by its acronym VHS, is the recording and playing standard for video cassette recorders (VCRs), developed by JVC and launched in 1976.
It became a standard format for consumer recording and viewing in the 1980s after competing in a fierce format war with Sony's Betamax and, to a lesser extent, Philips's Video 2000.
A VHS cassette contains a 12.65 mm (1/2-inch aprox.) wide magnetic tape which is wound from one of two spools to the other, allowing it to slowly pass by the reader head of the video cassette recorder.
Several improved versions of VHS exist, most notably S-VHS, an improved analog standard, and D-VHS, which records digital video onto a VHS form factor tape.
VHS-C tapes (C for compact) are used in some camcorders, and can be played back in standard VHS players with an adapter. Its development hampered the sales of the Betamax system somewhat, because the Betamax cassette geometry prevented a similar development.
VHS tapes have approximately 3 MHz of bandwidth, and about 240 vertical lines of resolution. The horizontal resolution of VHS (and all analog video systems) is determined by the TV standard - about 480 horizontal lines are visible in NTSC and about 576 lines in PAL.
Although VHS officially stands for Video Home System, it initially stood for Vertical Helical Scan, after the relative head/tape scan technique. Some early reports claimed that the initials originally stood for Victor Helical Scan system.
VCRs were taken to court and found legal in the case of Sony vs. Universal Studios.