Who Invented the Personal Computer?
The space shuttle was the most sophisticated and complicated space vehicle ever built. All of the vehicle's more than 2.5 million parts had to function perfectly for a safe mission to take place.
As sophisticated as the space shuttle looked on the outside, it was not nearly as complicated on the inside. The spacecraft and its entire launch sequence were controlled by five identical general purpose computers (GPCs) built by IBM. The GPCs had no more computational power than the 5150 personal computer invented by IBM in 1981 - the same year the space shuttle first flew.
That may sound a bit odd, but NASA took an "if it ain't broke, don't fix it" approach to the space shuttle's electronic brain. The vehicle's computers had to be simple, rugged enough to survive a launch, and extremely reliable. Updating the shuttle's programming for modern computers and debugging everything would have been extremely expensive.
The space agency upgraded the computers only once during the entire 30-year history of the program. In 1991, engineers doubled the memory size from 500 kilobytes to 1 megabyte. That makes the computers just 0.005 percent as powerful as an Xbox 360.
The space shuttle and the personal computer were both invented during the 1970s. While the origins of the shuttle are clear (it was commissioned by NASA and built by Rockwell International), the question of who invented the personal computer is more difficult to answer. As with many complex devices, it has many different fathers.
While early computers took up entire buildings, advances in microelectronics helped engineers shrink them down considerably by the time the Apollo Moon landings were completed in 1972. Hewlett Packard invented the first programmable computers that could fit on a desktop in the early 1970s. These desktop computers were programmed in the BASIC language and featured a keyboard. However, its graphical user interface was limited to a one-line screen.
In 1973, Wang and Xerox invented personal computers that resemble the personal computers we know today. The Wang 2200 featured a keyboard, cassette tape storage, and a monitor with a full-size cathode ray tube for display. The Xerox Alto had a computer screen that later inspired Microsoft Windows operating system and Apple Computer's Macintosh.
During this same period, engineers invented the microprocessor, which is a single chip containing all the circuitry that once fit inside of a large computer cabinet. At this point, personal computers began to really take off as increasingly powerful machines could be placed on desktops. The rapid progress in microprocessors led to Moore's Law, which states that the number of transistors that can be fit onto a chip doubles every two years.
With these technological advances, the Commodore PET became the first successfully mass marketed personal computer after it was introduced in January 1977. Apple introduced the Apple II in June of the same year, followed by the TRS-80 from Radio Shack in November.
By the time Columbia soared off the pad at the Kennedy Space Center in Florida for the first space shuttle mission in April 1981, personal computers were in offices and homes across the world.