Forth

An imperative, hierarchical stack based language with an almost quasi-religious following. Like so many languages at the time FORTH was initially spelled all caps, but it had become the custom to spell it as a noun as early as the mid 70's, unlike most contemporary languages.

A list of OS/2 implementations of Forth

• C-Forth - Open Source - Discontinued.
• FIG Forth - Status unknown
• FORTH/2 - Shareware - Discontinued
• FORTH32 - Shareware - Discontinued
• LMI Forth-83 - Commercial - Discontinued - Cross development tool that runs on top of UR/FORTH.
• Portable Forth Environment - Open Source - Current
• UR/Forth - Commercial - Discontinued.

OS/2 editors with Forth support

• jEdit - Java based - FORTH syntax highlighting built in - Current.

A list of DOS implementations of Forth

• Ale Forth - Freeware - Discontinued.
• BBL - Freeware - Discontinued.
• bigForth - Commercial - Discontinued.
• C-Forth - Open Source - Discontinued.
• ciforth - Open source - Current.
• ColorForth - Open source - Current.
• eForth - Open source - Sort of current .....
• FIG Forth - Open Source - Discontinued.
• F-PC - Open source - Discontinued.
• Forth Express - Commercial - Discontinued.
• Forthmacs - Commercial - Discontinued.
• FORTH32 - Shareware - Discontinued
• f83 - Open source - Discontinued.
• GForth - Open source - Discontinued.
• Golden Porcupine Forth - Shareware - Discontinued.
• HENCE4TH - Open source - Discontinued.
• hForth - Open source - Discontinued.
• Hierarchical Music Specification Language - Commercial - Discontinued.
• HS/FORTH - Commercial - Discontinued.
• LMI Forth-83 - Commercial - Discontinued - Cross development tool that runs on top of UR/FORTH.
• MiniForth - Open source - Discontinued.
• MMS Forth - Commercial - Discontinued.
• Modular Forth - Commercial - Discontinued.
• OOF - Open source - Discontinued.
• Portable Forth Environment - Open Source - Current
• PowerForth - Commercial - Discontinued.
• polyFORTH - Commercial - Discontinued.
• Pigmy Forth - Open source.
• TCOM - Freeware - Discontinued.
• ThisForth - Open source - Discontinued.
• TIMBRE - Freeware - Discontinued.
• TURBO-Forth - Commercial - Discontinued.
• UniForth - Commercial - Discontinued.
• UR/Forth - Commercial - Discontinued.
• WPForth - Commercial - Discontinued.
• Zen - Open source - Discontinued.
• 4THCMP - Freeware - Discontinued.

A list of Forth implementations that run under WinOS/2

• Forthmacs - Commercial - Discontinued.
• ProForth - Commercial - Discontinued.
• WinForth - Commercial - Discontinued.

A list of Forth implementations that run under Java

• Delta Forth - Open source - Discontinued.
• J2EE Forth - Open source - Discontinued.

A list of Forth implementations in JavaScript

• wForth - Open source - Discontinued.

Publications

• Byte Magazine August 1980 - Harks from a time when Byte used to have language specific issues, this one is the Forth issue and has a couple of now classic articles.

Tutorials and other learning material

• Starting Forth - Free tutorial in PDF format.

Links

• FIG - Forth Interest Group
• Forth resources on Taygeta.com - Outdated but extensive.

USENET

• comp.lang.forth - Surprisingly popular - Go to the Google groups version if your ISP does not offer USENET access or you are otherwise newsgroup challenged in any way.

Built with Forth

• Raidfile - A DOS in-memory database.

Standards

Most early FORTH standards were informal and based on books and articles by the original language author or on work by sundry Forth Interest Groups.

• FORTH-77 more commonly known as just F77 was developed by the European Forth User Group and most European implementations of FORTH in the 1970's and 80's derive from this standard.
• fig-FORTH was defined by the "fig-Forth Installation Manual" for the fig-FORTH 6502 version released by FIG in latter half of the 70's with an update in 1980. Most if not all fig-FORTH compatible releases reference this document rather than the F77 standard, although a few reference a later fig-FORTH for the IBM PC document. You can read the text here.
• FORTH-79 more commonly known as just F79 is an extension to fig-FORTH and adds about 40 new functions most of the derived from the F77 standard, you can download the standard text here. It never became as popular as fig-FORTH and most IBM PC systems skipped this standard and went from fig to F84.
• The F83 standard was done by Henry Laxon and Mike Perry at the USA Forth Interest Group, this massively extends the Forth base, the language now had over 1000 functions in addition an extensive standard library. The size however meant that the 8 bit implementations never bothered to follow the F83 standard and it was only on DOS were it became popular simply due to the existence of a public domain implementation from FIG. You can read the F83 standard here
• ANS Forth - 1994 draft - Aka ANSI Forth.

Forth history

• Invented by Charles H. Moore in 1968.