QBasic is an

integrated development environment An integrated development environment (IDE) is a Application software, software application that provides comprehensive facilities for software development. An IDE normally consists of at least a source-code editor, build automation tools, an ...

(IDE) and interpreter for a variety of dialects of

BASIC Basic or BASIC may refer to: Science and technology * BASIC, a computer programming language * Basic (chemistry), having the properties of a base * Basic access authentication, in HTTP Entertainment * Basic (film), ''Basic'' (film), a 2003 film ...

which are based on

QuickBASIC Microsoft QuickBASIC (also QB) is an Integrated Development Environment (or IDE) and compiler for the BASIC programming language that was developed by Microsoft. QuickBASIC runs mainly on DOS, though there was also a short-lived version for the c ...

. Code entered into the IDE is compiled into an

intermediate representation An intermediate representation (IR) is the data structure or code used internally by a compiler or virtual machine to represent source code. An IR is designed to be conducive to further processing, such as optimization and translation. A "good" ...

(IR), and this IR is immediately executed on demand within the IDE. Like QuickBASIC, but unlike earlier versions of Microsoft BASIC, QBasic is a

structured programming Structured programming is a programming paradigm aimed at improving the clarity, quality, and development time of a computer program by making specific disciplined use of the structured control flow constructs of selection ( if/then/else) and repet ...

language, supporting constructs such as

subroutine In computer programming, a function (also procedure, method, subroutine, routine, or subprogram) is a callable unit of software logic that has a well-defined interface and behavior and can be invoked multiple times. Callable units provide a ...

Line number In computing, a line number is a method used to specify a particular sequence of characters in a text file. The most common method of assigning numbers to lines is to assign every line a unique number, starting at 1 for the first line, and increm ...

s, a concept often associated with BASIC, are supported for compatibility but are not considered good form, having been replaced by descriptive line labels. QBasic has limited support for user-defined data types ( structures), and several primitive types used to contain strings of text or numeric data. It supports various inbuilt functions. For its time, QBasic provided a state-of-the-art IDE, including a

debugger A debugger is a computer program used to test and debug other programs (the "target" programs). Common features of debuggers include the ability to run or halt the target program using breakpoints, step through code line by line, and display ...

with features such as on-the-fly expression evaluation and code modification.

History

QBasic was intended as a replacement for

GW-BASIC GW-BASIC is a dialect of the BASIC programming language developed by Microsoft from IBM BASICA. Functionally identical to BASICA, its BASIC interpreter is a fully self-contained executable and does not need the Cassette BASIC ROM found in the ori ...

. It was based on the earlier

4.5 compiler but without QuickBASIC's compiler and linker elements. Version 1.0 was shipped together with

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 op ...

5.0 and higher, as well as

Windows 95 Windows 95 is a consumer-oriented operating system developed by Microsoft and the first of its Windows 9x family of operating systems, released to manufacturing on July 14, 1995, and generally to retail on August 24, 1995. Windows 95 merged ...

, Windows NT 3.x, and Windows NT 4.0.

IBM International Business Machines Corporation (using the trademark IBM), nicknamed Big Blue, is an American Multinational corporation, multinational technology company headquartered in Armonk, New York, and present in over 175 countries. It is ...

recompiled QBasic and included it in PC DOS 5.x, as well as

OS/2 OS/2 is a Proprietary software, proprietary computer operating system for x86 and PowerPC based personal computers. It was created and initially developed jointly by IBM and Microsoft, under the leadership of IBM software designer Ed Iacobucci, ...

2.0 onwards. eComStation and ArcaOS, descended from OS/2 code, include QBasic 1.0. QBasic 1.1 is included with MS-DOS 6.x, and, without EDIT, in

Windows 98 Windows 98 is a consumer-oriented operating system developed by Microsoft as part of its Windows 9x family of Microsoft Windows operating systems. It was the second operating system in the 9x line, as the successor to Windows 95. It was Software ...

and

Windows Me Windows Me (Millennium Edition) is an operating system developed by Microsoft as part of its Windows 9x family of Microsoft Windows operating systems. It was the successor to Windows 98, and was released to manufacturing on June 19, 2000, and t ...

. Starting with

Windows 2000 Windows 2000 is a major release of the Windows NT operating system developed by Microsoft, targeting the server and business markets. It is the direct successor to Windows NT 4.0, and was Software release life cycle#Release to manufacturing (RT ...

, Microsoft no longer includes QBasic with their operating systems.

QBasic (as well as the built-in MS-DOS Editor) is backward-compatible with DOS releases prior to 5.0 (down to at least DOS 3.20). However, if used on any 8088/

8086 The 8086 (also called iAPX 86) is a 16-bit microprocessor chip designed by Intel between early 1976 and June 8, 1978, when it was released. The Intel 8088, released July 1, 1979, is a slightly modified chip with an external 8-bit data bus (allo ...

computers, or on some 80286 computers, the QBasic program may run very slowly, or perhaps not at all, due to DOS memory size limits. Until MS-DOS 7, MS-DOS Editor and

Help Help may refer to: Arts, entertainment, and media Films * Help (2010 film), ''Help'' (2010 film), a Bollywood horror film * Help (2021 theatrical film), ''Help'' (2021 theatrical film), a British psychological thriller film * Help (2021 TV ...

required QBasic: the EDIT.COM and HELP.COM programs simply started QBasic in editor-and-help mode only, and these can also be entered by running QBASIC.EXE with the /EDITOR and /QHELP switches (i.e., command lines QBASIC /EDITOR and QBASIC /QHELP). QBasic came complete with four pre-written example programs. These were '' Nibbles'', a variant of the

Snake Snakes are elongated limbless reptiles of the suborder Serpentes (). Cladistically squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales much like other members of the group. Many species of snakes have s ...

game; '' Gorillas'', an artillery game; '' MONEY MANAGER'', a personal finance manager; and ''RemLine'', a Q-BASIC code line-number-removing program. QBasic has an

Easter egg Easter eggs, also called Paschal eggs, are eggs that are decorated for the Christian holiday of Easter, which celebrates the resurrection of Jesus. As such, Easter eggs are commonly used during the season of Eastertide (Easter season). The ...

accessed by pressing and holding simultaneously after running QBasic at the DOS prompt but before the title screen loads: this lists ''The Team'' of programmers.

References

External links

Runnable QBasic 1.1
via the Internet Archives
Download QBASIC 1.1 from the Internet Archive

QB Express: Qbasic and Freebasic programming magazine
* : created in 1997, one of the oldest QBasic sites on the web

an introduction {{Authority control BASIC interpreters Discontinued Microsoft BASICs DOS software Articles with example BASIC code 1991 software BASIC programming language family Microsoft programming languages Programming languages created in 1991

History

Contents

See also

References

External links