John G. Kemeny was the math department chairman at Dartmouth College, and largely on his reputation as an innovator in math teaching, in 1959 they won an Alfred P. Sloan Foundation award for $500,000 to build a new department building. Thomas E. Kurtz had joined the department in 1956, and from the 1960s they agreed on the need for programming literacy among students outside the traditional STEM fields. Kemeny later noted that “Our vision was that every student on campus should have access to a computer, and any faculty member should be able to use a computer in the classroom whenever appropriate. It was as simple as that."
Kemeny and Kurtz had made two previous experiments with simplified languages, DARSIMCO (Dartmouth Simplified Code) and DOPE (Dartmouth Oversimplified Programming Experiment). These did not progress past a single freshman class. New experiments using Fortran and ALGOL followed, but Kurtz concluded these languages were too tricky for what they desired. As Kurtz noted, Fortran had numerous oddly-formed commands, notably an "almost impossible-to-memorize convention for specifying a loop: 'DO 100, I = 1, 10, 2'. Is it '1, 10, 2' or '1, 2, 10', and is the comma after the line number required or not?"
Moreover, the lack of any sort of immediate feedback was a key problem; the machines of the era used batch processing and took long times to complete a run of a program. Kurtz suggested that time sharing offered a solution; a single machine could divide up its processing time among many users, giving them the illusion of having a slow computer to themselves. Small programs would return results in a few seconds. This led to increasing interest in a system using time-sharing and a new language specifically for use by non-STEM students.
Kemeny wrote the first version of BASIC. The acronym BASIC comes from the name of an unpublished paper by Thomas Kurtz. The new language was heavily patterned on FORTRAN II; statements were one-to-a-line, numbers were used to indicate the target of loops and branches, and many of the commands were similar or identical. However, the syntax was changed wherever it could be improved. For instance, the difficult to remember
DO loop was replaced by the much easier to remember
FOR I = 1 TO 10 STEP 2, and the line number used in the DO was instead indicated by the
NEXT I.[a] Likewise, the cryptic
IF statement of Fortran, whose syntax matched a particular instruction of the machine it was originally written on, became the simpler
IF I=5 THEN GOTO 100. These changes made the language much less idiosyncratic while still having an overall structure and feel similar to the original FORTRAN.
The project received a $300,000 grant from the National Science Foundation, which was used to purchase a GE-225 computer for processing, and a Datanet-30 realtime processor to handle the Teletype Model 33 teleprinters used for input and output. A team of a dozen undergraduates worked on the project for about a year, writing both the DTSS system and the BASIC compiler. The main CPU was later replaced by a GE-235, and still later by a GE-635
The first version BASIC language was released on 1 May 1964.
One of the graduate students on the implementation team was Sr. Mary Kenneth Keller, one of the first people in the U.S. to earn a PhD in computer science and the first woman to do so.
Initially, BASIC concentrated on supporting straightforward mathematical work, with matrix arithmetic support from its initial implementation as a batch language, and character string functionality being added by 1965.
Wanting use of the language to become widespread, its designers made the compiler available free of charge. (In the 1960s, software became a chargeable commodity; until then, it was provided without charge as a service with the very expensive computers, usually available only to lease.) They also made it available to high schools in the Hanover, New Hampshire area and put considerable effort into promoting the language. In the following years, as other dialects of BASIC appeared, Kemeny and Kurtz's original BASIC dialect became known as Dartmouth BASIC.