GW BASIC, more commonly known as GW-BASIC, is a variation of the BASIC programming language developed by Microsoft. It was designed for the IBM PC and is very similar to the IBM BASICA programming language, but it is a self-contained executable and unlike other BASIC derived languages; it does not need the ROM BASIC.
GW-BASIC includes many features such as the CLS command for clearing the screen, PRINT USING and LPRINT commands; WHILE-WEND loops, INKEY$ function for reading keystrokes, IN/OUT instructions for I/O, error trapping capabilities, and much more.
First used in 1983, Microsoft bundled GW BASIC with the MS-DOS operating systems on IBM compatible computers. Microsoft also developed and released a BASIC compiler called BASCOM, which was compatible with GW BASIC.