Quick BASIC

Microsoft QuickBASIC (often abbreviated correctly as QB or incorrectly as QBasic) is a descendant of the BASIC programming language that Microsoft Corporation developed for use with the MS-DOS operating system, together with other programming products such as QuickC or QuickPascal. It was loosely based on GW-BASIC but added user-defined types, improved programming structures, better graphics and disk support, and a compiler in addition to the interpreter. Microsoft released QuickBasic as a commercial development package.

History

Microsoft released the first version of QuickBASIC on August 18, 1985, on a single 5.25" floppy disk. QuickBASIC used a radically different integrated development environment (IDE) than the one that came with earlier versions of BASIC. Line numbers were no longer necessary as users could insert and remove lines directly through an on-screen text editor.

QuickBASIC included the "PC BASIC Compiler", which was used to compile programs into DOS executables. The editor had an interpreter with which the user could run a program without having to close the editor at all, and could be used to debug a program before creating the executable file. There were some small differences between the interpreter and the compiler, so that programs that ran perfectly in the interpreter did not run in their compiled version or did not compile at all.

In 1987 Borland released Turbo BASIC, a compiler compatible with Quick BASIC, marketed under the names First BASIC and PowerBASIC starting in 1989.

The last version of QuickBASIC was 4.5 released in 1988, although it was further developed as the Professional Development System (PDS), whose latest version was 7.1 in October 1990. The PDS version was also sometimes called QuickBASIC eXtended (QBX). The successor to QuickBASIC and PDS was Visual Basic 1.0, which came out in 1991 in two incompatible versions, one for DOS and one for Windows. Later versions of Visual Basic did not include DOS versions, as Microsoft wanted developers to focus on Windows applications.

Starting with MS-DOS 5, versions of DOS included a GW-BASIC replacement based on QuickBASIC 4.5. That replacement was called QBASIC, developed in 1991. Compared to QuickBASIC, QBASIC is limited in that it lacks a few functions, can only handle programs of a limited size, has no support for separate modules, and is interpreter-only. Lacking a compiler, it cannot directly produce executable programs, although programs developed with QBASIC can be compiled using QuickBasic 4.5, PDS 7.1, or VBDOS 1.0, if one is available.

Although the software was discontinued by Microsoft, re-implementations of the language have emerged under GNU licenses, such as FreeBASIC or QB64.