I feel obliged to mention Loeliger's Threaded Interpretive Languages. It really helped me figure out what was going on under the hood w/ FORTH. That might be

I feel obliged to mention Loeliger's Threaded Interpretive Languages. It really helped me figure out what was going on under the hood w/ FORTH. That might be my only "beef" w/ FORTH back in the day, introductory documentation was easy to find, but intermediate and advanced documentation was much harder to come by. Forth, Inc. now has a number of decent books. Check them out at https://www.forth.com/forth-books/ https://www.forth.com/forth-books/ . And the Internet Archive has plenty of FORTH books: https://archive.org/search.php?query=FORTH https://archive.org/search.php?query=FORTH . And the FORTH Interest Group has links to most everything else: http://www.forth.org/ http://www.forth.org/ . And let me echo the sentiment that it's delightful to have a programming language you could probably implement in a weekend and understand every bit of what's going on under the hood.