BASIC, the Beginner's All-purpose Symbolic Instruction Code, ran its first programs at Dartmouth College in New Hampshire on 1 May 1964. Its designers, mathematics professors John G. Kemeny and Thomas E. Kurtz, wanted every Dartmouth student to be able to use a computer, including those studying history or English. That goal explains why BASIC was invented at Dartmouth College and why it looks the way it does: short keywords, line numbers, and almost nothing to set up before your first program runs.
Why BASIC was invented at Dartmouth College
In the early 1960s, using a computer usually meant punching cards, handing them to an operator and waiting hours for a printout. Languages like FORTRAN were designed for scientists and engineers. Kemeny and Kurtz believed computing would matter to everyone, so they tackled two problems at once:
- Access. They built the Dartmouth Time-Sharing System (DTSS) on a General Electric GE-225 computer with a Datanet-30 communications processor, so many students could type at teletype terminals simultaneously and get answers in seconds.
- Simplicity. They designed a language a non-specialist could learn in an afternoon, with English-like keywords such as
LET,PRINT,IF,GOTOandFOR, and error messages written for humans.
Undergraduates did much of the programming work on the system. In the early hours of 1 May 1964, two BASIC programs ran on DTSS at the same time, which is the date usually given as BASIC's birthday. Dartmouth soon connected local schools and colleges, and computing became an ordinary part of student life there.
Design and key features
Original Dartmouth BASIC was small. The first manual described around fifteen statements. A few design choices stand out:
- Line numbers served as both labels for
GOTOand the way you edited a program at a teletype: retype a line number to replace that line. - No declarations. Variables were a letter, optionally followed by a digit, and all numbers were floating point, so beginners never had to think about integer versus real types.
- Compiled, not interpreted. Many people assume BASIC was always interpreted, but Dartmouth BASIC was compiled and run as soon as you typed
RUN, which made it fast enough for a shared machine. - Matrix operations (
MATstatements) were added early, reflecting its mathematical origins.
A short BASIC example
10 REM SUM OF SQUARES FROM 1 TO 10
20 LET S = 0
30 FOR I = 1 TO 10
40 LET S = S + I * I
50 NEXT I
60 PRINT "SUM OF SQUARES ="; S
70 ENDThis program prints 385. It would run, with little or no change, on Dartmouth BASIC in the 1960s and on most home computers of the early 1980s.
From time-sharing to home computers
General Electric offered BASIC on its commercial time-sharing service, and other vendors soon followed, notably DEC on its PDP minicomputers. The real explosion came with microcomputers.
| Year | Milestone |
|---|---|
| 1964 | Dartmouth BASIC runs on the GE-225 |
| 1975 | Altair BASIC by Bill Gates, Paul Allen and Monte Davidoff; Microsoft's first product |
| 1977 | Apple II, Commodore PET and TRS-80 ship with BASIC |
| 1978 | ANSI standard for Minimal BASIC |
| 1981 | BBC BASIC on the Acorn BBC Micro |
| 1985 | Kemeny and Kurtz release True BASIC |
| 1991 | Microsoft Visual Basic 1.0 |
For a whole generation, switching on a computer meant seeing a BASIC prompt. Magazines printed program listings for readers to type in, and many professional programmers wrote their first lines this way. The downside was fragmentation: each manufacturer's dialect had its own graphics and sound commands, and many dropped Dartmouth's structured improvements.
Criticism and legacy
BASIC had famous critics. Edsger Dijkstra wrote in 1975 that students exposed to BASIC were "mentally mutilated beyond hope of regeneration", a jab aimed largely at its reliance on GOTO. Kemeny and Kurtz themselves disliked the stripped-down microcomputer versions, which they called "Street BASIC", and created True BASIC as a structured, standard-conforming alternative. Later dialects such as QuickBASIC, BBC BASIC and Visual Basic added procedures, local variables and proper control structures.
Is BASIC still used today?
Classic line-numbered BASIC is now mostly a hobby and retrocomputing interest, but the family lives on. Visual Basic for Applications still automates countless Excel and Access workbooks, VB.NET remains supported by Microsoft, and open-source dialects such as FreeBASIC and QB64 are actively developed. The reasons why BASIC was invented at Dartmouth College, making programming reachable for ordinary people, are the same reasons educators now give for Scratch and Python.
Frequently asked questions
Who invented the BASIC programming language at Dartmouth?
BASIC was designed by John G. Kemeny and Thomas E. Kurtz, both mathematics professors at Dartmouth College. A team of undergraduate students helped write the compiler and the time-sharing system. Kemeny later served as Dartmouth's president.
Why did early BASIC use line numbers?
Users worked at teletype terminals with no screen editor, so line numbers were the way to insert, replace or delete lines. They also served as targets for GOTO and GOSUB. Later structured dialects made them optional.
Was the original Dartmouth BASIC free to use?
Kemeny and Kurtz wanted computing to be freely available to students, and Dartmouth did not charge students for using the system. The language spread quickly because it was simple to implement and widely copied. Commercial dialects, such as Microsoft's, were later sold as licensed products.
