Also hard to overstate the sheer impact of a tool like Excel, which in many ways is an ad-hoc programming tool so intuitive that anyone can learn to use it. Even though it sees more jeer than celebration, and is often something techies seek to liberate users from, it's likely one of the most economically impactful inventions of the 20th century, already delivering many of the things we hype AI for.

Entire businesses run off Excel spreadsheets.