A brief description of each implementation of Tcl listed in [Category Tcl Implementations]. ''(under construction)''

   * [Tcl] is the definitive implementation and is written in C.  The same code base can be used with different build options or targets, different sets of add-on packages, or different packaging (e.g. as a single binary file).  These variations are distributions of [Tcl] and are covered in [Category Distribution].

   * C, [TinyTcl] is a slimmed-down fork of Tcl 6.7
   * C, [ettcl] is a slimmed-down fork of Tcl 7.x
   * C, [Jim]
   * C, [Picol]
   * C++, [TinyTcl] (same name, different project) is a small interpreter written from scratch
   * Java, [Jacl]
   * Java, [Hecl]
   * JavaScript, [Tcl in JavaScript]
   * FORTRAN, [FEMTOL]
   * ''concept'', [HereTcl], [MicroTcl for Tcl9], [The Very Minimal Tcl Core Command Set]

Several of these implementations are intended to reduce the footprint of Tcl.  For a discussion of these small implementations, see [Small Tcl].

Implementations of languages that have recognisable similarities to Tcl:
   * tinker - see [TinyTcl]

Other systems listed on [Category Tcl Implementations] are not distinct implementations:
   * [Parenthetcl] is a Tcl/C hybrid for writing compiled Tcl extensions
   * [Tclkit] is really a [Tcl] distribution.  It is a single binary file that provides Tcl/Tk and a number of popular extensions.

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[Category Tcl Implementations]