Before the PC

The personal computer didn't begin in Boca Raton in 1981. Six years earlier, MITS shipped a build-it-yourself blue box called the Altair 8800 and accidentally launched an industry. By 1977 a trio of pre-built machines — the Apple II, the Commodore PET, and the Tandy TRS-80 — had carried personal computing out of the hobbyist garage and into the home and the schoolroom. This is the world IBM was about to disrupt.

• 
  1975

  MITS Altair 8800

  MITS · Intel 8080 @ 2 MHz

  A blue-and-grey metal box covered in toggle switches and red LEDs.

• 
  1977

  Apple II

  Apple Computer · MOS Technology 6502 @ 1.023 MHz

  Steve Wozniak's design: a single-board computer with eight expansion slots, color graphics, and a built-in BASIC.

• 
  1977

  Commodore PET 2001

  Commodore International · MOS Technology 6502 @ 1 MHz

  The first all-in-one home computer: monitor, keyboard, and datassette all in a single metal case.

• 
  1977

  Tandy TRS-80 Model I

  Tandy / Radio Shack · Zilog Z80 @ 1.77 MHz

  Sold through Radio Shack's thousands of retail stores, which gave it instant nationwide distribution that Apple and Commodore couldn't match.

• 
  1979

  Atari 800

  Atari, Inc. · MOS 6502B @ 1.79 MHz

  Atari's flagship 8-bit home computer.