British computer scientist and Internet Hall of Fame inductee Peter Kirstein died in January 2020 at the age of 86, after a nearly 50-year career at UCL. A few years before he died, he was commissioned by then Conversation technology editor Michael Parker (now director of operations) to write an in-depth piece originally intended as part of a special series on the internet. It wasn’t published at the time, as the series was postponed, but now to mark Professor Kirsten’s contributions we are deli...