Daniel noticed it before Mom did.

His homework app has it. The search engine has it. She used it to write an email last week. AI went from something you heard about in science fiction to something inside almost every app, almost overnight.

Or so it seemed.

Here is what most people do not realize. AI itself is not new. Scientists have been working on it since the 1950s. For decades it could do specific things well -- recognize a face in a photo, recommend a movie, beat a human at chess. But it could not hold a conversation. It could not write an essay. It could not explain something in plain language that felt genuinely useful.

What changed is two things happening close together.

First -- the technology got dramatically better. Researchers developed a new way of training AI on language, called a transformer, that let  ...