[ErikHuisman]

This is a 5 year old video about how search works. They are already talking about using machine learning for ranking wich is kinda like AI depending on your definition.

https://www.youtube.com/watch?v=LVV_93mBfSU

[marginalia_nu]

If you want a more in-depth walkthrough, this is a good resource: https://ciir.cs.umass.edu/irbook/