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BASIC (Beginners' All-purpose Symbolic Instruction Code) is a family of
general-purpose,
high-level programming language
In computer science, a high-level programming language is a programming language with strong Abstraction (computer science), abstraction from the details of the computer. In contrast to low-level programming languages, it may use natural language ...
s designed for ease of use.
The original version was created by
John G. Kemeny
John George Kemeny (born Kemény János György; May 31, 1926 – December 26, 1992) was a Kingdom of Hungary (1920–1946), Hungarian-born Americans, American mathematician, computer scientist, and educator best known for co-developing the BASIC ...
and
Thomas E. Kurtz at
Dartmouth College
Dartmouth College (; ) is a private research university in Hanover, New Hampshire. Established in 1769 by Eleazar Wheelock, it is one of the nine colonial colleges chartered before the American Revolution. Although founded to educate Native A ...
in 1963. They wanted to enable students in non-scientific fields to use computers. At the time, nearly all computers required writing custom software, which only
scientist
A scientist is a person who conducts Scientific method, scientific research to advance knowledge in an Branches of science, area of the natural sciences.
In classical antiquity, there was no real ancient analog of a modern scientist. Instead, ...
s and
mathematician
A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems.
Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change.
History
On ...
s tended to learn.
In addition to the program language, Kemeny and Kurtz developed the
Dartmouth Time Sharing System
The Dartmouth Time-Sharing System (DTSS) is a discontinued operating system first developed at Dartmouth College between 1963 and 1964. It was the first successful large-scale time-sharing system to be implemented, and was also the system for wh ...
(DTSS), which allowed multiple users to edit and run BASIC programs simultaneously on remote terminals. This general model became very popular on
minicomputer
A minicomputer, or colloquially mini, is a class of smaller general purpose computers that developed in the mid-1960s and sold at a much lower price than mainframe and mid-size computers from IBM and its direct competitors. In a 1970 survey, ...
systems like the
PDP-11
The PDP-11 is a series of 16-bit minicomputers sold by Digital Equipment Corporation (DEC) from 1970 into the 1990s, one of a set of products in the Programmed Data Processor (PDP) series. In total, around 600,000 PDP-11s of all models were sold, ...
and
Data General Nova
The Data General Nova is a series of 16-bit minicomputers released by the American company Data General. The Nova family was very popular in the 1970s and ultimately sold tens of thousands of units.
The first model, known simply as "Nova", was ...
in the late 1960s and early 1970s.
Hewlett-Packard
The Hewlett-Packard Company, commonly shortened to Hewlett-Packard ( ) or HP, was an American multinational information technology company headquartered in Palo Alto, California. HP developed and provided a wide variety of hardware components ...
produced an entire computer line for this method of operation, introducing the
HP2000
The HP 2100 is a series of 16-bit minicomputers that were produced by Hewlett-Packard (HP) from the mid-1960s to early 1990s. Tens of thousands of machines in the series were sold over its twenty-five year lifetime, making HP the fourth largest mi ...
series in the late 1960s and continuing sales into the 1980s. Many early video games trace their history to one of these versions of BASIC.
The emergence of
microcomputer
A microcomputer is a small, relatively inexpensive computer having a central processing unit (CPU) made out of a microprocessor. The computer also includes memory and input/output (I/O) circuitry together mounted on a printed circuit board (PC ...
s in the mid-1970s led to the development of multiple BASIC dialects, including
Microsoft BASIC
Microsoft BASIC is the foundation software product of the Microsoft company and evolved into a line of BASIC interpreters and compiler(s) adapted for many different microcomputers. It first appeared in 1975 as Altair BASIC, which was the first ve ...
in 1975. Due to the tiny
main memory
Computer data storage is a technology consisting of computer components and recording media that are used to retain digital data. It is a core function and fundamental component of computers.
The central processing unit (CPU) of a computer ...
available on these machines, often 4 KB, a variety of
Tiny BASIC
Tiny BASIC is a family of dialects of the BASIC programming language that can fit into 4 or fewer KBs of memory. Tiny BASIC was designed in response to the open letter published by Bill Gates complaining about users pirating Altair BASIC, which ...
dialects were also created. BASIC was available for almost any system of the era, and became the ''de facto'' programming language for
home computer systems that emerged in the late 1970s. These
PCs almost always had a
BASIC interpreter
A BASIC interpreter is an interpreter that enables users to enter and run programs in the BASIC language and was, for the first part of the microcomputer era, the default application that computers would launch. Users were expected to use the BAS ...
installed by default, often in the machine's
firmware
In computing, firmware is a specific class of computer software that provides the low-level control for a device's specific hardware. Firmware, such as the BIOS of a personal computer, may contain basic functions of a device, and may provide h ...
or sometimes on a
ROM
Rom, or ROM may refer to:
Biomechanics and medicine
* Risk of mortality, a medical classification to estimate the likelihood of death for a patient
* Rupture of membranes, a term used during pregnancy to describe a rupture of the amniotic sac
* ...
cartridge.
BASIC declined in popularity in the 1990s, as more powerful microcomputers came to market and programming languages with advanced features (such as
Pascal
Pascal, Pascal's or PASCAL may refer to:
People and fictional characters
* Pascal (given name), including a list of people with the name
* Pascal (surname), including a list of people and fictional characters with the name
** Blaise Pascal, Fren ...
and
C) became tenable on such computers. In 1991,
Microsoft
Microsoft Corporation is an American multinational technology corporation producing computer software, consumer electronics, personal computers, and related services headquartered at the Microsoft Redmond campus located in Redmond, Washing ...
released
Visual Basic Visual Basic is a name for a family of programming languages from Microsoft. It may refer to:
* Visual Basic .NET (now simply referred to as "Visual Basic"), the current version of Visual Basic launched in 2002 which runs on .NET
* Visual Basic (cl ...
, combining an updated version of BASIC with a
visual forms builder. This reignited use of the language and "VB" remains a major programming language in the forms of
VBA and
VB.NET
Visual Basic, originally called Visual Basic .NET (VB.NET), is a multi-paradigm, object-oriented programming language, implemented on .NET, Mono, and the .NET Framework. Microsoft launched VB.NET in 2002 as the successor to its original Visua ...
.
Origin
John G. Kemeny
John George Kemeny (born Kemény János György; May 31, 1926 – December 26, 1992) was a Kingdom of Hungary (1920–1946), Hungarian-born Americans, American mathematician, computer scientist, and educator best known for co-developing the BASIC ...
was the math department chairman at Dartmouth College. Based largely on his reputation as an innovator in math teaching, in 1959 the school 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 Kemeny and Kurtz agreed on the need for programming literacy among students outside the traditional
STEM
Stem or STEM may refer to:
Plant structures
* Plant stem, a plant's aboveground axis, made of vascular tissue, off which leaves and flowers hang
* Stipe (botany), a stalk to support some other structure
* Stipe (mycology), the stem of a mushro ...
fields. Kemeny later noted that "Our vision was that every student on campus should have access to a
computer
A computer is a machine that can be programmed to Execution (computing), carry out sequences of arithmetic or logical operations (computation) automatically. Modern digital electronic computers can perform generic sets of operations known as C ...
, 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)
DOPE, short for Dartmouth Oversimplified Programming Experiment, was a simple programming language designed by John Kemény in 1962 to offer students a transition from flow-charting to programming the LGP-30. Lessons learned from implementing DO ...
. These did not progress past a single freshman class. New experiments using
Fortran and
ALGOL
ALGOL (; short for "Algorithmic Language") is a family of imperative computer programming languages originally developed in 1958. ALGOL heavily influenced many other languages and was the standard method for algorithm description used by the ...
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: . 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
Computerized batch processing is a method of running software programs called jobs in batches automatically. While users are required to submit the jobs, no other interaction by the user is required to process the batch. Batches may automatically ...
and took a long time to complete a run of a program. While Kurtz was visiting
MIT
The Massachusetts Institute of Technology (MIT) is a private land-grant research university in Cambridge, Massachusetts. Established in 1861, MIT has played a key role in the development of modern technology and science, and is one of the m ...
,
John McCarthy suggested that
time-sharing
In computing, time-sharing is the sharing of a computing resource among many users at the same time by means of multiprogramming and multi-tasking.DEC Timesharing (1965), by Peter Clark, The DEC Professional, Volume 1, Number 1
Its emergence a ...
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.
[, p. 23] 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
An acronym is a word or name formed from the initial components of a longer name or phrase. Acronyms are usually formed from the initial letters of words, as in ''NATO'' (''North Atlantic Treaty Organization''), but sometimes use syllables, as ...
''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 to Fortran. However, the
syntax
In linguistics, syntax () is the study of how words and morphemes combine to form larger units such as phrases and sentences. Central concerns of syntax include word order, grammatical relations, hierarchical sentence structure ( constituency) ...
was changed wherever it could be improved. For instance, the difficult to remember
DO
loop was replaced by the much easier to remember , and the line number used in the DO was instead indicated by the
NEXT I
. Likewise, the cryptic
IF
statement of Fortran, whose syntax matched a particular instruction of the machine on which it was originally written, became the simpler . 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
The National Science Foundation (NSF) is an independent agency of the United States government that supports fundamental research and education in all the non-medical fields of science and engineering. Its medical counterpart is the National I ...
, which was used to purchase a
GE-225 computer for processing, and a Datanet-30 realtime processor to handle the
Teletype Model 33
The Teletype Model 33 is an electromechanical teleprinter designed for light-duty office use. It is less rugged and cost less than earlier Teletype machines. The Teletype Corporation introduced the Model 33 as a commercial product in 1963 after ...
teleprinter
A teleprinter (teletypewriter, teletype or TTY) is an electromechanical device that can be used to send and receive typed messages through various communications channels, in both point-to-point and point-to-multipoint configurations. Initia ...
s 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 first version BASIC language was released on 1 May 1964.
Initially, BASIC concentrated on supporting straightforward mathematical work, with
matrix
Matrix most commonly refers to:
* ''The Matrix'' (franchise), an American media franchise
** ''The Matrix'', a 1999 science-fiction action film
** "The Matrix", a fictional setting, a virtual reality environment, within ''The Matrix'' (franchis ...
arithmetic support from its initial implementation as a batch language, and
character string
In computer programming, a string is traditionally a sequence of characters, either as a literal constant or as some kind of variable. The latter may allow its elements to be mutated and the length changed, or it may be fixed (after creation). ...
functionality being added by 1965. Usage in the university rapidly expanded, requiring the main CPU to be replaced by a GE-235, and still later by a GE-635. By the early 1970s there were hundreds of terminals connected to the machines at Dartmouth, some of them remotely.
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
Hanover is a town located along the Connecticut River in Grafton County, New Hampshire, United States. As of the 2020 census, its population was 11,870. The town is home to the Ivy League university Dartmouth College, the U.S. Army Corps of Eng ...
area and regionally throughout New England on Teletype Model 33 and Model 35 teleprinter terminals connected to Dartmouth via dial-up phone lines, and they 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
Dartmouth BASIC is the original version of the BASIC programming language. It was designed by two professors at Dartmouth College, John G. Kemeny and Thomas E. Kurtz. With the underlying Dartmouth Time Sharing System (DTSS), it offered an inter ...
''.
New Hampshire recognized the accomplishment in 2019 when it erected a highway historical marker in Hanover describing the creation of "the first user-friendly programming language".
Spread on time-sharing services
The emergence of BASIC took place as part of a wider movement towards time-sharing systems. First conceptualized during the late 1950s, the idea became so dominant in the computer industry by the early 1960s that its proponents were speaking of a future in which users would "buy time on the computer much the same way that the average household buys power and water from utility companies".
[Bauer, W. F., ]
Computer design from the programmer's viewpoint
'' (Eastern Joint Computer Conference, December 1958) One of the first descriptions of computer time-sharing.
General Electric, having worked on the Dartmouth project, wrote their own underlying operating system and launched an online time-sharing system known as Mark I. It featured BASIC as one of its primary selling points. Other companies in the emerging field quickly followed suit;
Tymshare
Tymshare, Inc (Matthew Heyer-Baker) was a time-sharing service and third-party hardware maintenance company competing with companies such as CompuServe, Service Bureau Corporation and National CSS. Tymshare developed or acquired various technolog ...
introduced
SUPER BASIC
SUPER BASIC, sometimes SBASIC for short, is an advanced dialect of the BASIC programming language offered on Tymshare's SDS 940 systems starting in 1968 and available well into the 1970s.
Like the Dartmouth BASIC it was based on, SUPER BASIC wa ...
in 1968,
CompuServe
CompuServe (CompuServe Information Service, also known by its initialism CIS) was an American online service provider, the first major commercial one in the world – described in 1994 as "the oldest of the Big Three information services (the oth ...
had a version on the
DEC-10 at their launch in 1969, and by the early 1970s BASIC was largely universal on general-purpose
mainframe computers
A mainframe computer, informally called a mainframe or big iron, is a computer used primarily by large organizations for critical applications like bulk data processing for tasks such as censuses, industry and consumer statistics, enterpris ...
. Even
IBM eventually joined the club with the introduction of VS-BASIC in 1973.
Although time-sharing services with BASIC were successful for a time, the widespread success predicted earlier was not to be. The emergence of minicomputers during the same period, and especially low-cost microcomputers in the mid-1970s, allowed anyone to purchase and run their own systems rather than buy online time which was typically billed at dollars per minute.
Spread on minicomputers
![ESO Hewlett Packard 2116 minicomputer](https://upload.wikimedia.org/wikipedia/commons/c/c3/ESO_Hewlett_Packard_2116_minicomputer.jpg)
BASIC, by its very nature of being small, was naturally suited to porting to the
minicomputer
A minicomputer, or colloquially mini, is a class of smaller general purpose computers that developed in the mid-1960s and sold at a much lower price than mainframe and mid-size computers from IBM and its direct competitors. In a 1970 survey, ...
market, which was emerging at the same time as the time-sharing services. These machines had very small
main memory
Computer data storage is a technology consisting of computer components and recording media that are used to retain digital data. It is a core function and fundamental component of computers.
The central processing unit (CPU) of a computer ...
, perhaps as little as 4 KB in modern terminology, and lacked high-performance storage like
hard drive
A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnet ...
s that make compilers practical. On these systems, BASIC was normally implemented as an interpreter rather than a compiler due to the reduced need for working memory.
A particularly important example was
HP Time-Shared BASIC
HP Time-Shared BASIC (HP TSB) is a BASIC programming language interpreter for Hewlett-Packard's HP 2000 line of minicomputer-based time-sharing computer systems. TSB is historically notable as the platform that released the first public versio ...
, which, like the original Dartmouth system, used two computers working together to implement a time-sharing system. The first, a low-end machine in the
HP 2100
The HP 2100 is a series of 16-bit minicomputers that were produced by Hewlett-Packard (HP) from the mid-1960s to early 1990s. Tens of thousands of machines in the series were sold over its twenty-five year lifetime, making HP the fourth largest mi ...
series, was used to control user input and save and load their programs to tape or disk. The other, a high-end version of the same underlying machine, ran the programs and generated output. For a cost of about $100,000, one could own a machine capable of running between 16 and 32 users at the same time.
The system, bundled as the HP 2000, was the first mini platform to offer time-sharing and was an immediate runaway success, catapulting HP to become the third-largest vendor in the minicomputer space, behind
DEC and
Data General
Data General Corporation was one of the first minicomputer firms of the late 1960s. Three of the four founders were former employees of Digital Equipment Corporation (DEC).
Their first product, 1969's Data General Nova, was a 16-bit minicomputer ...
(DG).
DEC, the leader in the minicomputer space since the mid-1960s, had initially ignored BASIC. This was due to their work with
RAND Corporation
The RAND Corporation (from the phrase "research and development") is an American nonprofit global policy think tank created in 1948 by Douglas Aircraft Company to offer research and analysis to the United States Armed Forces. It is financed ...
, who had purchased a
PDP-6
The PDP-6, short for Programmed Data Processor model 6, is a computer developed by Digital Equipment Corporation (DEC) during 1963 and first delivered in the summer of 1964.
It was an expansion of DEC's existing 18-bit systems to use a 36-bit da ...
to run their
JOSS Joss may refer to:
* Joss (name), including a list of people with the name
* JOSS, a time-sharing programming language
* Joss (Chinese statue), a religious object
* Joss JP1, an Australian-built supercar
* Joss paper, a type of burnt offering
* J ...
language, which was conceptually very similar to BASIC. This led DEC to introduce a smaller, cleaned up version of JOSS known as
FOCAL, which they heavily promoted in the late 1960s. However, with timesharing systems widely offering BASIC, and all of their competition in the minicomputer space doing the same, DEC's customers were clamoring for BASIC. After management repeatedly ignored their pleas,
David H. Ahl
David H. Ahl (born May 17, 1939) is an American author who is the founder of ''Creative Computing (magazine), Creative Computing'' magazine. He is also the author of many how-to books, including ''BASIC Computer Games'', the first computer book t ...
took it upon himself to buy a BASIC for the
PDP-8
The PDP-8 is a 12-bit computing, 12-bit minicomputer that was produced by Digital Equipment Corporation, Digital Equipment Corporation (DEC). It was the first commercially successful minicomputer, with over 50,000 units being sold over the model's ...
, which was a major success in the education market. By the early 1970s, FOCAL and JOSS had been forgotten and BASIC had become almost universal in the minicomputer market. DEC would go on to introduce their updated version,
BASIC-PLUS
BASIC-PLUS is an extended dialect of the BASIC programming language that was developed by Digital Equipment Corporation (DEC) for use on its RSTS/E time-sharing operating system for the PDP-11 series of 16-bit minicomputers in the early 1970s thro ...
, for use on the
RSTS/E
RSTS () is a multi-user time-sharing operating system developed by Digital Equipment Corporation (DEC, now part of Hewlett-Packard) for the PDP-11 series of 16-bit minicomputers. The first version of RSTS (RSTS-11, Version 1) was implemented in 1 ...
time-sharing operating system.
During this period a number of simple
text-based game
A text game or text-based game is an electronic game that uses a text-based user interface, that is, the user interface employs a set of encodable characters,
such as ASCII, instead of bitmap or vector graphics.
All text-based games have been ...
s were written in BASIC, most notably Mike Mayfield's ''
Star Trek
''Star Trek'' is an American science fiction media franchise created by Gene Roddenberry, which began with the eponymous 1960s television series and quickly became a worldwide pop-culture phenomenon. The franchise has expanded into vari ...
''. David Ahl collected these, some ported from FOCAL, and published them in an educational newsletter he compiled. He later collected a number of these into book form, ''101 BASIC Computer Games'', published in 1973.
During the same period, Ahl was involved in the creation of a small computer for education use, an early
personal computer
A personal computer (PC) is a multi-purpose microcomputer whose size, capabilities, and price make it feasible for individual use. Personal computers are intended to be operated directly by an end user, rather than by a computer expert or tec ...
. When management refused to support the concept, Ahl left DEC in 1974 to found the seminal computer magazine, ''
Creative Computing
''Creative Computing'' was one of the earliest magazines covering the microcomputer revolution. Published from October 1974 until December 1985, the magazine covered the spectrum of hobbyist/home/personal computing in a more accessible format th ...
''. The book remained popular, and was re-published on several occasions.
Explosive growth: the home computer era
![Pn-pravez-class-5](https://upload.wikimedia.org/wikipedia/commons/1/18/Pn-pravez-class-5.jpg)
The introduction of the first
microcomputer
A microcomputer is a small, relatively inexpensive computer having a central processing unit (CPU) made out of a microprocessor. The computer also includes memory and input/output (I/O) circuitry together mounted on a printed circuit board (PC ...
s in the mid-1970s was the start of explosive growth for BASIC. It had the advantage that it was fairly well known to the young designers and computer hobbyists who took an interest in microcomputers, many of whom had seen BASIC on minis or mainframes. Despite
Dijkstra's famous judgement in 1975, "It is practically impossible to teach good programming to students that have had a prior exposure to BASIC: as potential programmers they are mentally mutilated beyond hope of regeneration", BASIC was one of the few languages that was both high-level enough to be usable by those without training and small enough to fit into the microcomputers of the day, making it the ''de facto'' standard programming language on early microcomputers.
The first
microcomputer version of BASIC was co-written by
Bill Gates
William Henry Gates III (born October 28, 1955) is an American business magnate and philanthropist. He is a co-founder of Microsoft, along with his late childhood friend Paul Allen. During his career at Microsoft, Gates held the positions ...
,
Paul Allen
Paul Gardner Allen (January 21, 1953 – October 15, 2018) was an American business magnate, computer programmer, researcher, investor, and philanthropist. He co-founded Microsoft Corporation with childhood friend Bill Gates in 1975, which h ...
and
Monte Davidoff
Monte Davidoff (; born 1956) is an American computer programmer.
Davidoff is from Glendale, Wisconsin. He graduated from Nicolet High School in 1974, and went on to Harvard College, where he majored in applied mathematics, the department at Harva ...
for their newly formed company, Micro-Soft. This was released by MITS in
punch tape
Five- and eight-hole punched paper tape
Paper tape reader on the Harwell computer with a small piece of five-hole tape connected in a circle – creating a physical program loop
Punched tape or perforated paper tape is a form of data storage ...
format for the
Altair 8800
The Altair 8800 is a microcomputer designed in 1974 by MITS and based on the Intel 8080 CPU. Interest grew quickly after it was featured on the cover of the January 1975 issue of Popular Electronics and was sold by mail order through advertiseme ...
shortly after the machine itself, immediately cementing BASIC as the primary language of early microcomputers. Members of the
Homebrew Computer Club
The Homebrew Computer Club was an early computer hobbyist group in Menlo Park, California, which met from March 1975 to December 1986. The club had an influential role in the development of the microcomputer revolution and the rise of that asp ...
began circulating copies of the program, causing Gates to write his
Open Letter to Hobbyists
Open or OPEN may refer to:
Music
* Open (band), Australian pop/rock band
* The Open (band), English indie rock band
* ''Open'' (Blues Image album), 1969
* ''Open'' (Gotthard album), 1999
* ''Open'' (Cowboy Junkies album), 2001
* ''Open'' ( ...
, complaining about this early example of
software piracy
Copyright infringement (at times referred to as piracy) is the use of works protected by copyright without permission for a usage where such permission is required, thereby infringing certain exclusive rights granted to the copyright holder, su ...
.
Partially in response to Gates's letter, and partially to make an even smaller BASIC that would run usefully on 4 KB machines,
Bob Albrecht
Bob Albrecht is a key figure in the early history of microcomputers. He was one of the founders of the People's Computer Company and its associated newsletters which turned into '' Dr. Dobb's Journal.'' He also brought the first Altair 8800 to t ...
urged
Dennis Allison
Dennis Allison is a lecturer at Stanford University, a position he has held since 1976.
Allison was a founding member of the People's Computer Company.
Allison in 1975 wrote a specification for a microcomputer interpreter (computing), interpre ...
to write their own variation of the language. How to design and implement a stripped-down version of an
interpreter for the BASIC language was covered in articles by Allison in the first three quarterly issues of the ''
People's Computer Company
People's Computer Company (PCC) was an organization, a newsletter (the ''People's Computer Company Newsletter'') and, later, a quasiperiodical called the ''Dragonsmoke''. PCC was founded and produced by Dennis Allison, Bob Albrecht and George Fire ...
'' newsletter published in 1975 and implementations with source code published in ''
Dr. Dobb's Journal of Tiny BASIC Calisthenics & Orthodontia: Running Light Without Overbyte''. This led to a wide variety of
Tiny BASIC
Tiny BASIC is a family of dialects of the BASIC programming language that can fit into 4 or fewer KBs of memory. Tiny BASIC was designed in response to the open letter published by Bill Gates complaining about users pirating Altair BASIC, which ...
s with added features or other improvements, with versions from Tom Pittman and
Li-Chen Wang
Li-Chen Wang (born 1935) is an American computer engineer, best known for his ''Palo Alto Tiny BASIC'' for Intel 8080-based microcomputers. He was a member of the Homebrew Computer Club and made significant contributions to the software for early ...
becoming particularly well known.
Micro-Soft, by this time
Microsoft
Microsoft Corporation is an American multinational technology corporation producing computer software, consumer electronics, personal computers, and related services headquartered at the Microsoft Redmond campus located in Redmond, Washing ...
, ported their interpreter for the
MOS 6502
The MOS Technology 6502 (typically pronounced "sixty-five-oh-two" or "six-five-oh-two") William Mensch and the moderator both pronounce the 6502 microprocessor as ''"sixty-five-oh-two"''. is an 8-bit microprocessor that was designed by a small te ...
, which quickly become one of the most popular microprocessors of the 8-bit era. When new microcomputers began to appear, notably the "1977 trinity" of the
TRS-80
The TRS-80 Micro Computer System (TRS-80, later renamed the Model I to distinguish it from successors) is a desktop microcomputer launched in 1977 and sold by Tandy Corporation through their Radio Shack stores. The name is an abbreviation of '' ...
,
Commodore PET
The Commodore PET is a line of personal computers produced starting in 1977 by Commodore International. A single all-in-one case combines a MOS Technology 6502 microprocessor, Commodore BASIC in read-only memory, keyboard, monochrome monitor, an ...
and
Apple II
The Apple II (stylized as ) is an 8-bit home computer and one of the world's first highly successful mass-produced microcomputer products. It was designed primarily by Steve Wozniak; Jerry Manock developed the design of Apple II's foam-m ...
, they either included a version of the MS code, or quickly introduced new models with it. By 1978, MS BASIC was a ''de facto'' standard and practically every
home computer of the 1980s included it in
ROM
Rom, or ROM may refer to:
Biomechanics and medicine
* Risk of mortality, a medical classification to estimate the likelihood of death for a patient
* Rupture of membranes, a term used during pregnancy to describe a rupture of the amniotic sac
* ...
. Upon boot, a BASIC interpreter in
direct mode
In computing, direct or immediate mode in an interactive programming system is the immediate execution of commands, statements, or expressions. In many interactive systems, most of these can both be included in programs or executed directly in ...
was presented.
Commodore Business Machines
Commodore International (other names include Commodore International Limited) was an American home computer and electronics manufacturer founded by Jack Tramiel. Commodore International (CI), along with its subsidiary Commodore Business Mach ...
included
Commodore BASIC
Commodore BASIC, also known as PET BASIC or CBM-BASIC, is the dialect of the BASIC programming language used in Commodore International's 8-bit home computer line, stretching from the PET of 1977 to the C128 of 1985.
The core is based on 6502 M ...
, based on Microsoft BASIC. The Apple II and TRS-80 each had two versions of BASIC, a smaller introductory version introduced with the initial releases of the machines and an MS-based version introduced as interest in the platforms increased. As new companies entered the field, additional versions were added that subtly changed the BASIC family. The
Atari 8-bit family
The Atari 8-bit family is a series of 8-bit home computers introduced by Atari, Inc. in 1979 as the Atari 400 and Atari 800. The series was successively upgraded to Atari 1200XL , Atari 600XL, Atari 800XL, Atari 65XE, Atari 130XE, Atari 800XE, ...
had its own
Atari BASIC
Atari BASIC is an interpreter (computing), interpreter for the BASIC programming language that shipped with the Atari 8-bit family of MOS Technology 6502, 6502-based home computers. Unlike most American BASICs of the home computer era, Atari BAS ...
that was modified in order to fit on an 8 KB
ROM cartridge
A ROM cartridge, usually referred to in context simply as a cartridge, cart, or card, is a replaceable part designed to be connected to a consumer electronics device such as a home computer, video game console or, to a lesser extent, electroni ...
.
Sinclair BASIC
Sinclair BASIC is a dialect of the programming language BASIC used in the 8-bit home computers from Sinclair Research and Timex Sinclair. The Sinclair BASIC interpreter was made by Nine Tiles Networks Ltd.
History
Sinclair BASIC was orig ...
was introduced in 1980 with the Sinclair
ZX80
The Sinclair ZX80 is a home computer launched on 29 January 1980 by Science of Cambridge Ltd. (later to be better known as Sinclair Research). It is notable for being one of the first computers available in the United Kingdom for less than a h ...
, and was later extended for the Sinclair
ZX81
The ZX81 is a home computer that was produced by Sinclair Research and manufactured in Dundee, Scotland, by Timex Corporation. It was launched in the United Kingdom in March 1981 as the successor to Sinclair's ZX80 and designed to be a low-cost ...
and the Sinclair
ZX Spectrum
The ZX Spectrum () is an 8-bit computing, 8-bit home computer that was developed by Sinclair Research. It was released in the United Kingdom on 23 April 1982, and became Britain's best-selling microcomputer.
Referred to during development as t ...
. The
BBC #REDIRECT BBC #REDIRECT BBC
Here i going to introduce about the best teacher of my life b BALAJI sir. He is the precious gift that I got befor 2yrs . How has helped and thought all the concept and made my success in the 10th board exam. ...
...
published
BBC BASIC
BBC BASIC is a version of the BASIC programming language released in 1981 as the native programming language for the BBC Micro home/personal computer, providing a standardized language for a UK computer literacy project of the BBC. It was wri ...
, developed by
Acorn Computers
Acorn Computers Ltd. was a British computer company established in Cambridge, England, in 1978. The company produced a number of computers which were especially popular in the United Kingdom, UK, including the Acorn Electron and the Acorn Archi ...
Ltd, incorporating many extra
structured programming
Structured programming is a programming paradigm aimed at improving the clarity, quality, and development time of a computer program by making extensive use of the structured control flow constructs of selection ( if/then/else) and repetition ( ...
keywords and advanced floating-point operation features.
As the popularity of BASIC grew in this period, computer magazines published complete source code in BASIC for video games, utilities, and other programs. Given BASIC's straightforward nature, it was a simple matter to
type in the code from the magazine and execute the program. Different magazines were published featuring programs for specific computers, though some BASIC programs were considered universal and could be used in machines running any variant of BASIC (sometimes with minor adaptations). Many books of type-in programs were also available, and in particular, Ahl published versions of the original 101 BASIC games converted into the Microsoft dialect and published it from ''Creative Computing'' as ''
BASIC Computer Games
''BASIC Computer Games'' is a compilation of type-in computer games in the BASIC programming language collected by David H. Ahl. Some of the games were written or modified by Ahl as well. Among its better-known games are '' Hamurabi'' and '' Sup ...
''. This book, and its sequels, provided hundreds of ready-to-go programs that could be easily converted to practically any BASIC-running platform.
The book reached the stores in 1978, just as the
home computer market was starting off, and it became the first million-selling computer book. Later packages, such as
Learn to Program BASIC
Learning is the process of acquiring new understanding, knowledge, behaviors, skills, values, attitudes, and preferences. The ability to learn is possessed by humans, animals, and some machines; there is also evidence for some kind of learnin ...
would also have gaming as an introductory focus. On the business-focused
CP/M
CP/M, originally standing for Control Program/Monitor and later Control Program for Microcomputers, is a mass-market operating system created in 1974 for Intel 8080/ 85-based microcomputers by Gary Kildall of Digital Research, Inc. Initial ...
computers which soon became widespread in small business environments,
Microsoft BASIC
Microsoft BASIC is the foundation software product of the Microsoft company and evolved into a line of BASIC interpreters and compiler(s) adapted for many different microcomputers. It first appeared in 1975 as Altair BASIC, which was the first ve ...
(
MBASIC
MBASIC is the Microsoft BASIC implementation of BASIC for the CP/M operating system. MBASIC is a descendant of the original Altair BASIC interpreters that were among Microsoft's first products. MBASIC was one of the two versions of BASIC bundled w ...
) was one of the leading applications.
In 1978, David Lien published the first edition of ''The BASIC Handbook: An Encyclopedia of the BASIC Computer Language'', documenting keywords across over 78 different computers. By 1981, the second edition documented keywords from over 250 different computers, showcasing the explosive growth of the microcomputer era.
IBM PC and compatibles
![IBM Cassette BASIC](https://upload.wikimedia.org/wikipedia/commons/d/d1/IBM_Cassette_BASIC.png)
When IBM was designing the
IBM PC
The IBM Personal Computer (model 5150, commonly known as the IBM PC) is the first microcomputer released in the IBM PC model line and the basis for the IBM PC compatible de facto standard. Released on August 12, 1981, it was created by a team ...
, they followed the paradigm of existing home computers in wanting to have a built-in BASIC. They sourced this from Microsoft –
IBM Cassette BASIC
The IBM Personal Computer Basic, commonly shortened to IBM BASIC, is a programming language first released by IBM with the IBM Personal Computer, Model 5150 (IBM PC) in 1981. IBM released four different versions of the Microsoft BASIC interpre ...
– but Microsoft also produced several other versions of BASIC for
MS-DOS
MS-DOS ( ; acronym for Microsoft Disk Operating System, also known as Microsoft DOS) is an operating system for x86-based personal computers mostly developed by Microsoft. Collectively, MS-DOS, its rebranding as IBM PC DOS, and a few ope ...
/
PC DOS
PC or pc may refer to:
Arts and entertainment
* Player character or playable character, a fictional character controlled by a human player, usually in role-playing games or computer games
* ''Port Charles'', an American daytime TV soap opera
* ...
including IBM Disk BASIC (BASIC D), IBM BASICA (BASIC A), GW-BASIC (a BASICA-compatible version that did not need IBM's ROM) and QBasic, all typically bundled with the machine. In addition they produced the Microsoft BASIC Compiler aimed at professional programmers. Turbo
Pascal
Pascal, Pascal's or PASCAL may refer to:
People and fictional characters
* Pascal (given name), including a list of people with the name
* Pascal (surname), including a list of people and fictional characters with the name
** Blaise Pascal, Fren ...
-publisher Borland published Turbo Basic 1.0 in 1985 (successor versions are still being marketed by the original author under the name PowerBASIC). Microsoft wrote the windowed AmigaBASIC that was supplied with version 1.1 of the pre-emptive multitasking GUI Amiga computers (late 1985 / early 1986), although the product unusually did not bear any Microsoft marks.
These later variations introduced many extensions, such as improved string manipulation and graphics support, access to the file system and additional data types. More important were the facilities for
structured programming
Structured programming is a programming paradigm aimed at improving the clarity, quality, and development time of a computer program by making extensive use of the structured control flow constructs of selection ( if/then/else) and repetition ( ...
, including additional control structures and proper subroutines supporting local variables. However, by the latter half of the 1980s, users were increasingly using pre-made applications written by others rather than learning programming themselves; while professional programmers now had a wide range of more advanced languages available on small computers.
C and later C++ became the languages of choice for professional Shrink wrap contract, "shrink wrap" application development.
Visual Basic
In 1991, Microsoft introduced
Visual Basic Visual Basic is a name for a family of programming languages from Microsoft. It may refer to:
* Visual Basic .NET (now simply referred to as "Visual Basic"), the current version of Visual Basic launched in 2002 which runs on .NET
* Visual Basic (cl ...
, an evolutionary development of QuickBASIC. It included constructs from that language such as block-structured control statements, parameterized subroutines and optional Type system#STATIC, static typing as well as object oriented language, object-oriented constructs from other languages such as "With" and "For Each". The language retained some compatibility with its predecessors, such as the Dim keyword for declarations, "Gosub"/Return statements and optional line numbers which could be used to locate errors. An important driver for the development of Visual Basic was as the new macro language for Microsoft Excel, a spreadsheet program. To the surprise of many at Microsoft who still initially marketed it as a language for hobbyists, the language came into widespread use for small custom business applications shortly after the release of VB version 3.0, which is widely considered the first relatively stable version.
While many advanced programmers still scoffed at its use, VB met the needs of small businesses efficiently as by that time, computers running Windows 3.1 had become fast enough that many business-related processes could be completed "in the blink of an eye" even using a "slow" language, as long as large amounts of data were not involved. Many small business owners found they could create their own small, yet useful applications in a few evenings to meet their own specialized needs. Eventually, during the lengthy lifetime of VB3, knowledge of Visual Basic had become a marketable job skill. Microsoft also produced VBScript in 1996 and Visual Basic .NET in 2001. The latter has essentially the same power as C Sharp (programming language), C# and Java (programming language), Java but with syntax that reflects the original Basic language. The Integrated development environment, IDE, with its Event-driven programming, event-driven GUI builder, was also influential on other tools, most notably Borland Software's Delphi (software), Delphi for Object Pascal and its own descendants such as Lazarus (IDE), Lazarus.
Mainstream support for the final version 6.0 of the original Visual Basic ended on March 31, 2005, followed by extended support in March 2008. On March 11, 2020, Microsoft announced that evolution of the VB.NET language had also concluded, although it was still supported. Meanwhile, competitors exist such as Xojo and Gambas.
Post-1990 versions and dialects
Many other BASIC dialects have also sprung up since 1990, including the Open-source software, open source QB64 and FreeBASIC, inspired by QBasic, and the Visual Basic-styled RapidQ, Basic For Qt and Gambas. Modern commercial incarnations include PureBasic, PowerBASIC, Xojo, Monkey X and True BASIC (the direct successor to Dartmouth BASIC from a company controlled by Kurtz).
Several web-based simple BASIC interpreters also now exist, including Microsoft's Microsoft Small Basic, Small Basic. Many versions of BASIC are also now available for smartphones and tablets via the Apple App Store (iOS), App Store, or Google Play store for Android. On game consoles, an application for the Nintendo 3DS and Nintendo DSi called ''Petit Computer'' allows for programming in a slightly modified version of BASIC with DS button support. A version has also been released for Nintendo Switch.
Calculators
Variants of BASIC are available on graphing and otherwise programmable calculators made by Texas Instruments, HP, Casio, and others.
Windows command-line
QBasic, a version of Microsoft QuickBASIC without the linker to make EXE files, is present in the Windows NT and DOS-Windows 95 streams of operating systems and can be obtained for more recent releases like Windows 7 which do not have them. Prior to DOS 5, the Basic interpreter was GW-BASIC, GW-Basic. QuickBasic is part of a series of three languages issued by Microsoft for the home and office power user and small-scale professional development; QuickC and QuickPascal are the other two. For Windows 95 and 98, which do not have QBasic installed by default, they can be copied from the installation disc, which will have a set of directories for old and optional software; other missing commands like Exe2Bin and others are in these same directories.
Other
![Nintendo-Famicom-Family-Basic-Keyboard-wCart](https://upload.wikimedia.org/wikipedia/commons/f/fb/Nintendo-Famicom-Family-Basic-Keyboard-wCart.jpg)
The various Microsoft, Lotus, and Corel office suites and related products are programmable with Visual Basic in one form or another, including LotusScript, which is very similar to VBA 6. The Host Explorer terminal emulator uses WWB as a macro language; or more recently the programme and the suite in which it is contained is programmable in an in-house Basic variant known as Hummingbird Basic. The VBScript variant is used for programming web content, Outlook 97, Internet Explorer, and the Windows Script Host. WSH also has a Visual Basic for Applications (VBA) engine installed as the third of the default engines along with VBScript, JScript, and the numerous proprietary or open source engines which can be installed like PerlScript, a couple of Rexx-based engines, Python, Ruby, Tcl, Delphi, XLNT, PHP, and others; meaning that the two versions of Basic can be used along with the other mentioned languages, as well as LotusScript, in a WSF file, through the component object model, and other WSH and VBA constructions. VBScript is one of the languages that can be accessed by the 4Dos, 4NT, and Take Command enhanced shells. SaxBasic and WWB are also very similar to the Visual Basic line of Basic implementations. The pre-Office 97 macro language for Microsoft Word is known as WordBASIC. Excel 4 and 5 use Visual Basic itself as a macro language. Chipmunk Basic, an old-school interpreter similar to BASICs of the 1970s, is available for Linux, Microsoft Windows and macOS.
Legacy
The ubiquity of BASIC interpreters on personal computers was such that textbooks once included simple "Try It In BASIC" exercises that encouraged students to experiment with mathematical and computational concepts on classroom or home computers. Popular computer magazines of the day typically included type-in programs.
Futurist and sci-fi writer David Brin mourned the loss of ubiquitous BASIC in a 2006 ''Salon'' article as have others who first used computers during this era. In turn, the article prompted Microsoft to develop and release Microsoft Small Basic, Small Basic; it also inspired similar projects like Basic-256. Dartmouth College, Dartmouth held a 50th anniversary celebration for BASIC on 1 May 2014, as did other organisations; at least one organisation of VBA programmers organised a 35th anniversary observance in 1999.
Dartmouth College celebrated the 50th anniversary of the BASIC language with a day of events on April 30, 2014. A short documentary film was produced for the event.
Syntax
Typical BASIC keywords
Data manipulation
;
LET
: assigns a value (which may be the result of an expression (programming), expression) to a variable. In most dialects of BASIC,
LET
is optional, and a line with no other identifiable keyword will assume the keyword to be
LET
.
;
DATA
: holds a list of values which are assigned sequentially using the READ command.
;
READ
: reads a value from a
DATA
statement and assigns it to a variable. An internal pointer keeps track of the last
DATA
element that was read and moves it one position forward with each
READ
. Most dialects allow multiple variables as parameters, reading several values in a single operation.
;
RESTORE
: resets the internal pointer to the first
DATA
statement, allowing the program to begin
READ
ing from the first value. Many dialects allow an optional line number or ordinal value to allow the pointer to be reset to a selected location.
;
DIM
: Sets up an array.
Program flow control
;
IF ... THEN ...
: used to perform comparisons or make decisions. Early dialects only allowed a line number after the
THEN
, but later versions allowed any valid statement to follow.
ELSE
was not widely supported, especially in earlier versions.
;
FOR ... TO ... ... NEXT
: repeat a section of code a given number of times. A variable that acts as a counter, the "index", is available within the Control flow#Loops, loop.
;
WHILE ... WEND
and
REPEAT ... UNTIL
: repeat a section of code while the specified condition is true. The condition may be evaluated before each iteration of the loop, or after. Both of these commands are found mostly in later dialects.
;
DO ... LOOP
or
: repeat a section of code indefinitely or while/until the specified condition is true. The condition may be evaluated before each iteration of the loop, or after. Similar to
WHILE
, these keywords are mostly found in later dialects.
;
Goto, GOTO
: jumps to a numbered or labelled line in the program. Most dialects also allowed the form .
;
GOSUB ... RETURN
: jumps to a numbered or labelled line, executes the code it finds there until it reaches a
RETURN
command, on which it jumps back to the statement following the
GOSUB
, either after a colon, or on the next line. This is used to implement subroutines.
;
ON ... GOTO/GOSUB
: chooses where to jump based on the specified conditions. See Switch statement for other forms.
;
DEF FN
: a pair of keywords introduced in the early 1960s to define functions. The original BASIC functions were modelled on FORTRAN single-line functions. BASIC functions were one expression with variable arguments, rather than subroutines, with a syntax on the model of
DEF FND(x) = x*x
at the beginning of a program. Function names were originally restricted to FN, plus one letter, ''i.e.'', FNA, FNB ...
Input and output
;
LIST
: displays the full source code of the current program.
;
PRINT
: displays a message on the screen or other output device.
;
INPUT
: asks the user to enter the value of a variable. The statement may include a prompt message.
;
TAB
: used with
PRINT
to set the position where the next character will be shown on the screen or printed on paper.
AT
is an alternative form.
;
SPC
: prints out a number of space characters. Similar in concept to
TAB
but moves by a number of additional spaces from the current column rather than moving to a specified column.
Mathematical functions
;
ABS
: Absolute value
;
ATN
: Arctangent (result in radians)
;
COS
: Cosine (argument in radians)
;
EXP
: Exponential function
;
INT
: Integer part (typically floor function)
;
LOG
: Natural logarithm
;
RND
: Random number generation
;
SIN
: Sine (argument in radians)
;
SQR
: Square root
;
TAN
: Tangent (argument in radians)
Miscellaneous
;
REM
: holds a programmer's comment or REMark; often used to give a title to the program and to help identify the purpose of a given section of code.
;
USR
: transfers program control to a Machine code, machine language subroutine, usually entered as an alphanumeric String (computer science), string or in a list of DATA statements.
;
CALL
: alternative form of
USR
found in some dialects. Does not require an artificial parameter to complete the function-like syntax of
USR
, and has a clearly defined method of calling different routines in memory.
;
TRON
/
TROFF
: turns on display of each line number as it is run ("TRace ON"). This was useful for debugging or correcting of problems in a program. TROFF turns it back off again.
;
ASM
: some compilers such as Freebasic, Purebasic, and Powerbasic also support Inline assembler, inline assembly language, allowing the programmer to intermix high-level and low-level code, typically prefixed with "ASM" or "!" statements.
Data types and variables
Minimal versions of BASIC had only integer variables and one- or two-letter variable names, which minimized requirements of limited and expensive memory (RAM). More powerful versions had floating-point arithmetic, and variables could be labelled with names six or more characters long. There were some problems and restrictions in early implementations; for example, Applesoft BASIC allowed variable names to be several characters long, but only the first two were significant, thus it was possible to inadvertently write a program with variables "LOSS" and "LOAN", which would be treated as being the same; assigning a value to "LOAN" would silently overwrite the value intended as "LOSS". Keywords could not be used in variables in many early BASICs; "SCORE" would be interpreted as "SC" OR "E", where OR was a keyword. String (computer science), String variables are usually distinguished in many microcomputer dialects by having $ suffixed to their name as a Sigil (computer programming), sigil, and values are often identified as strings by being delimited by "double quotation marks". Arrays in BASIC could contain integers, floating point or string variables.
Some dialects of BASIC supported matrix (mathematics), matrices and matrix operations, which can be used to solve sets of simultaneous linear algebraic equations. These dialects would directly support matrix operations such as assignment, addition, multiplication (of compatible matrix types), and evaluation of a determinant. Many microcomputer BASICs did not support this data type; matrix operations were still possible, but had to be programmed explicitly on array elements.
Examples
Unstructured BASIC
New BASIC programmers on a home computer might start with a simple program, perhaps using the language's PRINT statement to display a message on the screen; a well-known and often-replicated example is The C Programming Language, Kernighan and Ritchie's "Hello, World!" program:
10 PRINT "Hello, World!"
20 END
An infinite loop could be used to fill the display with the message:
10 PRINT "Hello, World!"
20 GOTO 10
Note that the
END
statement is optional and has no action in most dialects of BASIC. It was not always included, as is the case in this example. This same program can be modified to print a fixed number of messages using the common
FOR...NEXT
statement:
10 LET N=10
20 FOR I=1 TO N
30 PRINT "Hello, World!"
40 NEXT I
Most first-generation BASIC versions, such as MSX BASIC and GW-BASIC, supported simple data types, loop cycles, and arrays. The following example is written for GW-BASIC, but will work in most versions of BASIC with minimal changes:
10 INPUT "What is your name: "; U$
20 PRINT "Hello "; U$
30 INPUT "How many stars do you want: "; N
40 S$ = ""
50 FOR I = 1 TO N
60 S$ = S$ + "*"
70 NEXT I
80 PRINT S$
90 INPUT "Do you want more stars? "; A$
100 IF LEN(A$) = 0 THEN GOTO 90
110 A$ = LEFT$(A$, 1)
120 IF A$ = "Y" OR A$ = "y" THEN GOTO 30
130 PRINT "Goodbye "; U$
140 END
The resulting dialog might resemble:
What is your name: Mike
Hello Mike
How many stars do you want: 7
*******
Do you want more stars? yes
How many stars do you want: 3
***
Do you want more stars? no
Goodbye Mike
The original Dartmouth Basic was unusual in having a matrix keyword, MAT. Although not implemented by most later microprocessor derivatives, it is used in this example from the 1968 manual
which averages the numbers that are input:
5 LET S = 0
10 MAT INPUT V
20 LET N = NUM
30 IF N = 0 THEN 99
40 FOR I = 1 TO N
45 LET S = S + V(I)
50 NEXT I
60 PRINT S/N
70 GO TO 5
99 END
Structured BASIC
Second-generation BASICs (for example, VSI BASIC for OpenVMS, VAX Basic, SuperBASIC, True BASIC, QuickBASIC,
BBC BASIC
BBC BASIC is a version of the BASIC programming language released in 1981 as the native programming language for the BBC Micro home/personal computer, providing a standardized language for a UK computer literacy project of the BBC. It was wri ...
, Pick operating system, Pick BASIC, PowerBASIC, Liberty BASIC and (arguably) COMAL) introduced a number of features into the language, primarily related to structured and procedure-oriented programming. Usually, line numbering is omitted from the language and replaced with label (computer science), labels (for GOTO) and subroutine, procedures to encourage easier and more flexible design.
In addition keywords and structures to support repetition, selection and procedures with local variables were introduced.
The following example is in Microsoft QuickBASIC:
REM QuickBASIC example
REM Forward declaration - allows the main code to call a
REM subroutine that is defined later in the source code
DECLARE SUB PrintSomeStars (StarCount!)
REM Main program follows
INPUT "What is your name: ", UserName$
PRINT "Hello "; UserName$
DO
INPUT "How many stars do you want: ", NumStars
CALL PrintSomeStars(NumStars)
DO
INPUT "Do you want more stars? ", Answer$
LOOP UNTIL Answer$ <> ""
Answer$ = LEFT$(Answer$, 1)
LOOP WHILE UCASE$(Answer$) = "Y"
PRINT "Goodbye "; UserName$
END
REM subroutine definition
SUB PrintSomeStars (StarCount)
REM This procedure uses a local variable called Stars$
Stars$ = STRING$(StarCount, "*")
PRINT Stars$
END SUB
Object-oriented BASIC
Third-generation BASIC dialects such as
Visual Basic Visual Basic is a name for a family of programming languages from Microsoft. It may refer to:
* Visual Basic .NET (now simply referred to as "Visual Basic"), the current version of Visual Basic launched in 2002 which runs on .NET
* Visual Basic (cl ...
, Xojo, Gambas, StarOffice Basic, BlitzMax and PureBasic introduced features to support object-oriented and event-driven programming paradigm. Most built-in procedures and functions are now represented as ''methods'' of standard objects rather than ''operators''. Also, the operating system became increasingly accessible to the BASIC language.
The following example is in Visual Basic .NET:
Public Module StarsProgram
Private Function Ask(prompt As String) As String
Console.Write(prompt)
Return Console.ReadLine()
End Function
Public Sub Main()
Dim userName = Ask("What is your name: ")
Console.WriteLine("Hello ", userName)
Dim answer As String
Do
Dim numStars = CInt(Ask("How many stars do you want: "))
Dim stars As New String("*"c, numStars)
Console.WriteLine(stars)
Do
answer = Ask("Do you want more stars? ")
Loop Until answer <> ""
Loop While answer.StartsWith("Y", StringComparison.OrdinalIgnoreCase)
Console.WriteLine("Goodbye ", userName)
End Sub
End Module
Standards
* ANSI/ISO/IEC Standard for Minimal BASIC:
** ANSI X3.60-1978 "For minimal BASIC"
** ISO/IEC 6373:1984 "Data Processing—Programming Languages—Minimal BASIC"
* Ecma International, ECMA-55 Minimal BASIC ''(withdrawn, similar to ANSI X3.60-1978)''
* ANSI/ISO/IEC Standard for Full BASIC:
** ANSI X3.113-1987 "Programming Languages Full BASIC"
** INCITS/ISO/IEC 10279-1991 (R2005) "Information Technology – Programming Languages – Full BASIC"
* ANSI/ISO/IEC Addendum Defining Modules:
** ANSI X3.113 Interpretations-1992 "BASIC Technical Information Bulletin # 1 Interpretations of ANSI 03.113-1987"
** ISO/IEC 10279:1991/ Amd 1:1994 "Modules and Single Character Input Enhancement"
* Ecma International, ECMA-116 BASIC ''(withdrawn, similar to ANSI X3.113-1987)''
Compilers and interpreters
See also
* List of BASIC dialects
Notes
References
General references
*
*
*
*
*
External links
*
*
*
{{DEFAULTSORT:Basic
BASIC programming language family,
American inventions
Articles with example BASIC code
Programming languages
Programming languages created in 1964
Programming languages with an ISO standard