Jack W. Crenshaw wrote the Let's Build a Compiler article series from 1988 - 1995. This document is a formatted version of that excellent non-technical introduction to compiler construction. These web pages were created in 2005, and port Mr. Crenshaw's original Pascal code for the 68000 under SK*OS to the Forth language on a 80x86 CPU, under Windows XP. The text files were downloaded from http://compilers.iecc.com/crenshaw/. They are highly recommended. In this transcript I have assumed a 32-bit, byte-addressing Forth, with 8-bit characters. Division is symmetric, not floored, and two's complement is assumed throughout. iForth works splendidly for it, but other Forths can do it too.