Shockingly, a few posts I made in 1991 on comp.lang.python can still be had at the following direct links today (the formerly used search URL on groups.google.com seems to fail on mobiles unless a desktop page is requested):
Prolog is a logic-programming language, in which computation takes the form of automated deduction. You can find a decent (if potentially biased) overview of it on Wikipedia.
I explored optimized implementations of Prolog before, during, and after grad school, and coded a complete implementation in 68000 assembler and C, which did normal and delayed tail-recursion optimization, sported variable modes and modules, resorted to CPU-cycle counts for speed, and ran quicker than the version used by the university at the time.
But please don't ask me to explain what the posts meant...