Yeah, ocr is a type of AI. The big advantage of modern techniques is that it can factor in context a bit better. It's the same principle but a different mechanism for how you know a red hexagon with S__P on it says stop, even if the sign is dented, a letter fully fell off, it's raining and dark.

It also means it's sometimes wildly inaccurate, like in cases where it's just so much more likely that it said something else. Like how on a bright sunny day, with perfect clarity, and a crisp new sign with extra good visuals, you'll hit the breaks for a sign that's a red hexagon that says §¥¢¶. It's just very unlikely that that would coincidentally be on a red hexagon near the road, so it's more likely you saw wrong and it was actually the normal thing.