UNIVAC Computer
The Universal Automatic Computer or UNIVAC was a computer milestone accomplished by Dr. Presper Eckert and Dr. John Mauchly, the pair that invented the ENIAC computer.
J Presper Eckert and John Mauchly, after leaving behind the The Moore School of Engineering to create their own computer business, establish the United States Census Bureau as their first client was. The Bureau required a new computer to handle with the exploding U.S. population (the outset of the noted baby boom). In April 1946, a $300,000 deposit was made to Eckert and Mauchly for the research into a new computer named the UNIVAC.
The research for the project went poorly, and it wasn't until 1948 that the actual conception and contract was finalized. The Census Bureau's cap for the undertaking was $400,000. J Presper Eckert and John Mauchly were ready to absorb any run over in costs in hopes of recovering from future sales and contracts, but the economics of the situation brought the inventors to the brink of failure.
The central complex of the UNIVAC was about the size of a one-car garage: fourteen feet by eight feet by eight feet high. It held the mercury memory unit and all the C.P.U. circuitry. The exterior of the unit was composed of hinged gray metal doors that could be opened to access the circuitry racks. In the middle of one of the long sides of the unit, there was a clear Plexiglas door to allow access to the heart of the system: it was a walk-in computer. The vacuum tubes produced an enormous amount of heat, so a high capacity cooled water and blower air conditioner system was necessary to cool the unit. In addition to the central complex, there were eight UNISERVO tape drives, an operator cabinet, and a console typewriter/printing machine. In the beginning printing was done offline by the UNIPRINTER, which resembled an overgrown typewriter with an attached tape drive. A much-needed 600 line per minute printer (at 130 characters per line) was added in 1954. The full system had 5200 vacuum tubes, weighed 29,000 pounds, and exhausted 125 kilowatts of electrical power.
The UNIVAC interpreted numbers in binary-coded decimal with 6 bits for each digit. It used Excess-3 notation where the binary value was three greater than the actual number, so that zero was 000011, one was 000100, two was 000101, and so forth. Excess-3 had been applied in the Bell Telephone Laboratories Model I Relay Calculator built in 1940. Excess-3 was chosen for the UNIVAC because it simplified the complementing (making negative) of numbers and made the carries come out correctly for digit-by-digit decimal addition. The UNIVAC's word size was 72 data bits, which held eleven digits plus a sign, plus one parity bit for each six data bits, giving a sum total of 84. The mercury delay line memory added up to 1000 words. In addition to numbers, the UNIVAC could present alphanumeric data (letters of the alphabet and some punctuation marks) using six bits for each character with twelve characters to the word. Codes were designated for the letters of the alphabet and punctuation marks, such as 010100 for A, 010101 for B, 010110 for C and so forth.
The UNIVAC possessed a high-degree of self-checking: all processing was done in duplicate by two sets of circuitry, and the outcomes were compared to be certain they were identical. The UNIVAC had the ability to store the control counter measure in memory, making it feasible for the stream of a program to go to a subprogram and then come back to where it was in the primary program. While the 72-bit word could suit numbers up to 11 digits, scientific calculations quite frequently used greater numbers. Subsequent computers would be designed with electronic circuits to execute calculations on figures in floating-point format, but the UNIVAC didn't have hardware instructions of this kind. Floating-point calculations could, however, be performed by way of software subprograms, making it feasible for the UNIVAC to do both scientific computing and business data processing.
Early on in the conception of the UNIVAC system, Eckert and Mauchly had realized that for the computer to be of value in managing the large masses of data utilized in many business applications, such as payroll or inventory control, it would require a fast input/output system. Since punched cards would be sluggish, the company formulated the UNISERVO tape units to be the main input/output devices for the computer. No punched card devices were supplied with the UNIVAC, so the UNITYPER data entry machine was produced. The data entry clerk typed on a keyboard, and the UNITYPER registered the values on a reel of metal tape. The computer possessed thousands of vacuum tubes, which processed a then-astounding 10,000 operations per second (compared to 5 billion per second for today's superfast chips).
On March 31, 1951, the Census Bureau took delivery of the first UNIVAC computer. The ultimate cost of building the first UNIVAC was near one million dollars, the equivalent of more than $8 million in today's money. Forty-six UNIVAC computers were built for both government and business enterprise uses. Remington Rand became the first American manufacturer of a commercial computer system. Their first non-government contract was for General Electric's Appliance Park facility in Louisville, Kentucky, who utilized the UNIVAC computer for a payroll department application.
In a promotional stunt, the UNIVAC computer was used to predict the outcome of the Eisenhower-Stevenson presidential race. The computer had correctly predicted that Eisenhower would win, but the news media decided to ignore the computer's prediction and announced that the UNIVAC had been stumped. When the truth was exposed, it was considered astounding that a computer could do what political forecasters could not, and the UNIVAC promptly became a household name. The original UNIVAC now sits in the Smithsonian Institution.
The development of modern computers, along with the High Speed Internet, have revolutionized how we communicate, do business, and exchange information. You can find more about the history of computers & the Internet at Velocity Guide.