Prolog is a programming language that was developed in the 1970s. It is a logic-based programming language, which is pretty different from your typical programming language. Instead of writing functions and then having the computer execute them, Prolog lets you write rules and it will try to deduce the answers to your questions.

It's a pretty wild concept, and there are tons of cool examples of what Prolog can do. Some examples are:

- A solver for Suduko puzzles: https://rosettacode.org/wiki/Sudoku#Prolog

- A simple game where you guess a person's age: https://rosettacode.org/wiki/Guess_the_number#Prolog

- A family tree program: https://rosettacode.org/wiki/Family_tree#Prolog