Forth (programming language) references on wikipedia
Forth_(programming_language) Forth is a structured, imperative, stack-based, computer programming language and programming environment. Forth is sometimes spelled in all capital letters following the customary usage during its earlier years, although the name is not an acronym.A procedural, stack-oriented and reflective programming language without type checking, Forth features both interactive execution of commands (making it suitable as a shell for systems that lack a more formal operating system) and the ability to compile sequences of commands for later execution.