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1975

MITS Altair 8800

MITS

MITS Altair 8800
Photo by Michael Holley, Wikimedia Commons, public domain · source

Specifications

CPU
Intel 8080 @ 2 MHz
Memory
256 bytes (expandable via S-100 cards)
Storage
None — programs entered via front panel switches
Display
16 red LEDs on the front panel
OS
None at launch; later: BASIC from Microsoft, CP/M
Intro price
$439 kit, $621 assembled

The machine

A blue-and-grey metal box covered in toggle switches and red LEDs. You programmed it by flipping switches one byte at a time. The Altair shipped as a mail-order kit from a small calculator company in Albuquerque and unexpectedly sold thousands of units after a January 1975 cover story in Popular Electronics.

Why it matters

Kicked off the entire personal computer industry. Bill Gates and Paul Allen wrote Altair BASIC for it — Microsoft's first product. The S-100 bus it introduced became the dominant hobbyist architecture for years.