The IBM PC arrives

On August 12, 1981, IBM shipped the model 5150 and unintentionally set the rules for the next forty years: x86 inside, an OS bought from a small Seattle company, a published technical reference, and slots anyone could build cards for. Compaq's clean-room BIOS in 1983 made the clone industry inevitable. Apple answered with the Macintosh in 1984. The Mac changed the conversation about what a computer should look and feel like; the PC quietly took over the world.

• 
  1981

  IBM PC (model 5150)

  IBM · Intel 8088 @ 4.77 MHz

  Designed in a year by a small team in Boca Raton, Florida, working outside IBM's normal processes.

• 
  1983

  IBM PC XT (model 5160)

  IBM · Intel 8088 @ 4.77 MHz

  The first IBM PC shipped with a built-in hard drive.

• 
  1983

  Compaq Portable

  Compaq Computer Corporation · Intel 8088 @ 4.77 MHz

  A 28-pound 'luggable' that ran the same software as the IBM PC, in a sewing-machine-style case with a fold-down keyboard.

• 
  1984

  Tandy 1000

  Tandy / Radio Shack · Intel 8088 @ 4.77 MHz (later 7.16 MHz)

  An IBM-compatible designed to be friendlier and cheaper than the IBM PC, sold through Radio Shack stores.

• 
  1984

  Apple Macintosh (128K)

  Apple Computer · Motorola 68000 @ 7.83 MHz

  Launched with the iconic '1984' Super Bowl commercial.