How a legendary programmer shows you can build a working code reader in 100 lines

Peter Norvig, a well-known computer scientist, published a tutorial on 21 June 2026 showing how to write a simple program that reads and runs another language called Lisp. It takes fewer than 100 lines. The tutorial walks through three stages: breaking text into pieces, organizing those pieces into instructions, and then executing them. The approach keeps things transparent—you can see how the computer actually understands and runs code.