04 February 2009
BASIC programming language
The invention: An interactive computer system and simple programming language that made it easier for nontechnical people to use computers. The people behind the invention: John G. Kemeny (1926-1992), the chairman of Dartmouth’s mathematics department Thomas E. Kurtz (1928- ), the director of the Kiewit Computation Center at Dartmouth Bill Gates (1955- ), a cofounder and later chairman of the board and chief operating officer of the Microsoft Corporation The Evolution of Programming The first digital computers were developed duringWorldWar II (1939-1945) to speed the complex calculations required for ballistics, cryptography, and other military applications. Computer technology developed rapidly, and the 1950’s and 1960’s saw computer systems installed throughout the world. These systems were very large and expensive, requiring many highly trained people for their operation. The calculations performed by the first computers were determined solely by their electrical circuits. In the 1940’s, The American mathematician John von Neumann and others pioneered the idea of computers storing their instructions in a program, so that changes in calculations could be made without rewiring their circuits. The programs were written in machine language, long lists of zeros and ones corresponding to on and off conditions of circuits. During the 1950’s, “assemblers” were introduced that used short names for common sequences of instructions and were, in turn, transformed into the zeros and ones intelligible to the computer. The late 1950’s saw the introduction of high-level languages, notably Formula Translation (FORTRAN), CommonBusinessOriented Language (COBOL), and Algorithmic Language (ALGOL), which used English words to communicate instructions to the computer. Unfortunately, these high-level languages were complicated; they required some knowledge of the computer equipment and were designed to be used by scientists, engineers, and other technical experts. Developing BASIC John G. Kemeny was chairman of the department of mathematics at Dartmouth College in Hanover, New Hampshire. In 1962, Thomas E. Kurtz, Dartmouth’s computing director, approached Kemeny with the idea of implementing a computer system at Dartmouth College. Both men were dedicated to the idea that liberal arts students should be able to make use of computers. Although the English commands of FORTRAN and ALGOL were a tremendous improvement over the cryptic instructions of assembly language, they were both too complicated for beginners. Kemeny convinced Kurtz that they needed a completely new language, simple enough for beginners to learn quickly, yet flexible enough for many different kinds of applications. The language they developed was known as the “Beginner’s Allpurpose Symbolic Instruction Code,” or BASIC. The original language consisted of fourteen different statements. Each line of a BASIC program was preceded by a number. Line numbers were referenced by control flow statements, such as, “IF X = 9 THEN GOTO 200.” Line numbers were also used as an editing reference. If line 30 of a program contained an error, the programmer could make the necessary correction merely by retyping line 30. Programming in BASIC was first taught at Dartmouth in the fall of 1964. Students were ready to begin writing programs after two hours of classroom lectures. By June of 1968, more than 80 percent of the undergraduates at Dartmouth could write a BASIC program. Most of them were not science majors and used their programs in conjunction with other nontechnical courses. Kemeny and Kurtz, and later others under their supervision, wrote more powerful versions of BASIC that included support for graphics on video terminals and structured programming. The creators of BASIC, however, always tried to maintain their original design goal of keeping BASIC simple enough for beginners. Consequences Kemeny and Kurtz encouraged the widespread adoption of BASIC by allowing other institutions to use their computer system and by placing BASIC in the public domain. Over time, they shaped BASIC into a powerful language with numerous features added in response to the needs of its users. What Kemeny and Kurtz had not foreseen was the advent of the microprocessor chip in the early 1970’s, which revolutionized computer technology. By 1975, microcomputer kits were being sold to hobbyists for well under a thousand dollars. The earliest of these was the Altair. That same year, prelaw studentWilliam H. Gates (1955- ) was persuaded by a friend, Paul Allen, to drop out of Harvard University and help create a version of BASIC that would run on the Altair. Gates and Allen formed a company, Microsoft Corporation, to sell their BASIC interpreter, which was designed to fit into the tiny memory of the Altair. It was about as simple as the original Dartmouth BASIC but had to depend heavily on the computer hardware. Most computers purchased for home use still include a version of Microsoft Corporation’s BASIC. See also BINAC computer; COBOL computer language; FORTRAN programming language; SAINT; Supercomputer.