According to the company, in just over three years, iTunes U downloads have exceeded 300 million making it one of the world’s most popular online educational catalogues.

Apple says that over 800 universities throughout the world have active iTunes U sites and nearly half of these distribute their content publicly through the iTunes Store.

“iTunes U makes it easy for people to discover and learn with content from many of the world’s top institutions,” said Eddy Cue, Apple’s VP of Internet Services. “With such a wide selection of educational material, we’re providing iTunes users with an incredible way to learn on their computer, iPhone, iPod or iPad.”

The portal gives anyone access to content from institutions such as Harvard, MIT, Cambridge, Oxford, University of Melbourne and Université de Montréal.

All iTunes U content is free and can be accessed via Mac, PC, iPhone, iPod Touch and iPad.

You can find out more about iTunes U here.