Date unknown

• Sony
  Sony
  , commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....
  
   launches the three-quarter-inch videotape
  Videotape
  A videotape is a recording of images and sounds on to magnetic tape as opposed to film stock or random access digital media. Videotapes are also used for storing scientific or medical data, such as the data produced by an electrocardiogram...
  
   format known as U-matic
  U-matic
  U-matic is an analog recording videocassette format first shown by Sony in prototype in October 1969, and introduced to the market in September 1971. It was among the first video formats to contain the videotape inside a cassette, as opposed to the various Reel-to-Reel or open-reel formats of the...
  
  .