The Bywater BASIC Interpreter (bwBASIC) implements a large superset of the ANSI Standard for Minimal BASIC (X3.60-1978) and a significant subset of the ANSI Standard for Full BASIC (X3.113-1987) in C.

BWBASIC is an original creation of Ted A. Campbell, who stopped working on it in 1993. Since then it has received contributions from other programmers: Jon B. Volkoff, Paul Edwards, Howard S. Wulf, Ken Martin and Jon Foster.

Inside program, type:

• help - show all commands available.
• help commandname - show help for a specific command.
• list - list source code for the program currently in memory
• run - executes the program in memory from the start.
• new - deletes the program in memory and clears all variables.
• load filename - loads an ASCII BASIC program into memory.
• save filename - saves the current program into the file "filename" in ASCII format.
• shell "command" - lets you run a SHELL or DOS command within bwbasic. For example, to list the contents of the current directory, in Linux type shell "ls -l", in Windows type shell "dir".
• quit - exits bwbasic.

The official repository is located at SourceForge. However, all available versions were transfered to GitHub, in order to create a history with the modifications of all versions. Some compiled versions are also available in the Releases section, with their respective source code.

Ken Martin (a.k.a. KenUnix) created versions 3.20a, 3.20b, 3.20c and 3.20d. Ken Martin's repositories for these versions are available in GitHub: 3.20a, 3.20b, 3.20c and 3.20d.

There is another repository, mantained by Ken Martin in partnership with Jon Foster (a.k.a. ChipMaster). It is stored in Ye Ol' p Shack. The duo of programmers created the versions 3.20f and 3.20g (apparently there was no version "3.20e").