exec.1
In Forth there are basically two types of words. Firstly thers is what we call a coded definition which is written entirely in assembler. This is usually a primative for some high level construct.
Secondly there are the high level definitions like the variable, the constant or the colon definition to name a few.
The entry point into each of these types of word is always low level assembler code. For high level definition, this assembler code is a call to the specific handler for that word.
For a colon definition the entry point will be a call to the low level primative 'docolon'. For a variable it is a call to 'dovariable'. The return address of this call will point to the body of the high level definition which the called primative will then interpret.
This source file contains most of the words used to execute Forth high level definitions. This is accomplished using a number of low level primatives to said high level definitions (such as variables and constants etc).