GWBasic

GW-BASIC was a dialect of BASIC developed by Microsoft from BASICA, originally for Compaq.It is compatible with Microsoft/IBM BASICA, but was disk based and did not require the resources of the ROM included on IBM's machines. It was bundled with  MS-DOS operating systems on IBM PC compatibles by Microsoft. Like other early microcomputer versions of BASIC, GW-BASIC lacked many of the structures needed for structured programming such as local variables, and GW-BASIC programs executed relatively slowly, due to the fact that it was an interpreted programming language. It did have a large number of graphics commands.
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