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The analytical engine was hopelessly complicated for its time and was never completed. But 117 years later, punched cards that were not to be folded, spindled or mutilated became the heart of software technology. In 1951 the U.S. Census Bureau used punched cards for UNIVAC I, the first commercial computer.
The cards, though, are virtually gone.
Various kinds of software now give instructions to computers. Systems software controls the parts of a computer, including the video screen, the central processing unit and the disc drives, and makes them work together. Though sold under obscure brand names like CP/M, MS-DOS and UNIX, systems software for personal computers can be highly profitable, and last year sales totaled $500 million.
A heated competition is currently going on among systems-software producers. Digital Research of Pacific Grove,
Calif, created the first popular one, CP/M, but it has been supplanted by MS-DOS, which was developed by Microsoft for the IBM Personal Computer. In addition, AT&T is promoting UNIX, a system particularly efficient at performing several different tasks at once and communicating with other computers.
The machines can receive instructions only in a series of Is and Os. In order to make it easier for people to communicate with the machines, scientists have developed programming languages that translate commands into Is and Os. There are more than a dozen software languages, each designed for different kinds of users and applications. The first widely accepted one, FORTRAN (FORmula TRANslation), was developed in 1956 by a team at IBM. It is used primarily on scientific and mathematical problems. BASIC (Beginner's All-purpose Symbolic Instruction Code), which was written by Dartmouth Professors John G. Kemeny and Thomas E. Kurtz, is well suited for relatively simple personal-computer programs. It is widely taught in high schools and colleges, and even in some elementary schools, because it is easy to learn and use. More difficult to master, but more precise, is Pascal, named for the 17th century French mathematician. The language Ada, after the Countess of Lovelace, is the standard of the U.S. Department of Defense. Grace Hopper, one of the pioneer programmers, created COBOL (COmmon Business-Oriented Language), which is the most widely used programming language for mainframe computers.
Now 77, Hopper works at the U.S.
Navy's computer center in Washington. Since the 1982 retirement of Admiral Hyman Rickover at 82, Commodore Hopper is the Navy's oldest officer on active duty.
She gets credit for coining the name of a ubiquitous computer phenomenon: the bug. In August 1945, while she and some associates were working at Harvard on an experimental machine called the Mark I, a circuit malfunctioned. A researcher using tweezers located and removed the problem: a 2-in. long moth. Hopper taped the offending insect into her logbook. Says she: "From then on, when anything went wrong with a computer, we said it had bugs in it."
(The moth is still under tape along with records of the experiment at the U.S. Naval Surface Weapons Center in