"Five years from now - on the web for free - you'll be able to find the best lectures in the world," the Microsoft billionaire said last year. And in Gates's opinion this extraordinary and constantly expanding digital smorgasbord of educational choices "will be better than any single university" in the world.

If it’s complex it can’t work until it’s empty.

A new search engine that presents content that is readable for both humans and machines.

Laptops in the classroom cartoon.