GWBASIC

GW-BASIC, commonly written GW-BASIC or GWBASIC, is a dialect of the BASIC programming language developed by Microsoft for IBM PC compatibles. It is a bytecode-like interpreter that runs under DOS, serving as the disk-based successor to BASICA.

First released in the early 1980s, GW-BASIC was distributed with MS-DOS during the 1980s and remained widely used through the early 1990s. It required DOS to manage memory and hardware access and did not rely on ROM BASIC.

The environment provides an interactive prompt and a basic editor for line-numbered programs. Programs could be saved as .BAS files, loaded with LOAD, edited, and run with RUN; common commands included LIST, NEW, SAVE, and LOAD. The language supports typical BASIC constructs such as variables, control flow (IF... THEN, FOR... NEXT, GOTO, GOSUB... RETURN), and simple input/output.

GW-BASIC included built-in capabilities for graphics and sound. A basic graphics library allowed drawing shapes and plotting, and the PLAY statement offered rudimentary music synthesis. It could interface with DOS for file I/O and external programs.

As development environments evolved, GW-BASIC was gradually superseded by QuickBASIC and QBASIC, and by modern IDEs. It was ultimately discontinued but remains of historical interest as an early widely used PC BASIC implementation; it can still be run via emulation or DOSBox.