Popular online lecture publisher TED has started posting content on iTunes U, Apple's free education platform.

Initial courses cover topics such as creative problem solving, understanding happiness, and climate change, although with TED's huge wealth of content more is sure to follow.

If you haven't heard of TED, it started out in 1984 as an annual conference but has grown into a huge online platform where users can watch 20-minute lectures on pretty much any topic they might be interested in. The acronym stands for Technology, Entertainment, Design.