Ancient Computers

• The idea of using machines to preform routine mathematical computations--perhaps surprisingly--is old. In 1901, archeologists discovered a strange bronze clock-like mechanism in a sunken ship in the Greek islands. Now scientists believe the clock-like mechanism to be the first analog (non-electronic) computer, dubbing it the "Antikythera Mechanism." Constructed of more than 30 precision gears, the Antikythera Mechanism is believed to have been used to to predict the movements of heavenly bodies, among other mathematical predictions.
  
  

Early 20th century computers

• By the 1940s, German, Japanese, British and U.S. cryptographers used various cryptology machines to send and receive coded messages. The infamous Enigma encrypting machine developed by the Germans was so effective at mathematically encoding messages, that the British only understood intercepted messages after they had captured an Enigma machine from the Germans.
  
  

"AC" machines

• The famous ENIAC and UNIVAC machines were among the very first electronic computers. ENIAC, or the Electronic Numerical Integrator And Calculator, powered up in 1946 and was used in some of the calculations to create the atomic bomb. UNIVAC, or the UNIVersal Automatic Computer, was used to predict the re-election of President Dwight D. Eisenhower.
  Both computers, however, were fallible, relying on an interdependent set of fragile vacuum tubes and switches. For example, ENIAC weighed some 27 tons and took up 1,000 square feet, yet still had less computing power than an average hand-held calculator does today.
  
  

1960's

• In the 1960s, commercial versions of the integrated circuit, or microchip, were available for purchase at fairly reasonable prices. Produced separately by Fairchild Semiconductor Corporation and Texas Instruments, microchips revolutionized computer construction. The major problems with earlier vacuum tubes and transistors were heat and space. The microprocessor not only addressed these problems, but was able to perform thousands more calculations per second than earlier computer components.
  
  

Apple

• Apple Computer, though not the first personal computer maker, revolutionized the computing industry by making computers relatively affordable. Apple I computers debuted in 1976, were handmade and sported a wooden chasis. Two hundred Apple Is later, Apple offered the new Apple II for purchase. The Apple II came with game paddles, an integrated keyboard and other user-friendly advancements that set the trend for later computers.
  
  

Microsoft

• In 1985, perhaps inspired by Apple's success, Microsoft introduced a new format called Windows to replace its ubiquitous DOS, or Disk Operating System. Two years in development, it bore an eerie resemblance to Apple's Macintosh interface, prompting many to accuse Microsoft founder Bill Gates of copying Apple. Windows also supported WYSIWYG word processing and a mouse-driven interface. Computing power continued to increase, but the interface has since remained relatively unchanged.