Anyone who hasn’t yet spotted the YouTube channel Numberphile (call yourself a maths fan?) would do well to check out its amazing selection of videos, all loosely themed around numbers – not all of which are integers, either – but now edging on giving up on that pretence and just continuing to post videos about interesting bits of maths.

The videos are made by Brady Haran, a filmmaker who runs an unbelievable number of different YouTube channels, on widely varying subjects – but who also has a great feel for mathematical concepts, and guides the mathematicians featured into crafting an interesting and well-explained summary of each topic, using intelligent questions and masterful editing. Mathematicians featured range from YouTube maths video veterans like James Grime, to research mathematicians and even some ridiculous impostors who write maths blogs. I visited Brady last week and filmed a few clips on different themes, which should gradually start appearing on the YouTube channel over a while.

Here’s a classic featuring Matt Parker, and everyone’s favourite big number:

[youtube url=http://www.youtube.com/watch?v=XTeJ64KD5cg]

Watch out for updates about future Numberphile videos, and check out the back catalogue of videos here.