[VLM]

Even deeper, something like regular expressions, how do they work?

Or shallower (sort of?) you can't sell a cookbook of "whats the regular expression in perl to match the first word of a sentance" because we have google for that, but you can sell a style guide type book like "Modern Perl" where you probably could google everything in that book, but it would take 1000 different searches and not have a common voice.