If you've ever wondered what Bitcoin is, this straightforward, no-nonsense doco is a great primer to get the basics as well as understand a little bit of the history (which in this case – as the technology developed through the mechanisms that gave rise to it – are concurrent events).

Bitcoin miner (ie someone with a setup of computers to generate the decentralised digital currency) Daniel Mross and his filmmaker brother Nicholas start by explaining the concept behind Bitcoins, then track the spectacular rise and subsequent growing pains – everything from online theft to arrests – of the movement and the entrepreneurs who got in on the ground floor. You don't have to know much about how Bitcoins work to know how little governments like anything they can't regulate.

By the time of the film's conclusion, it had grown even too big for the Mross brothers to do very much with. Because of the mechanism of mining (ie generating and earning bitcoins), you now need an incredible amount of computing power crunching the data – more than you ever did before and more than the dedicated server set-up Mross deploys in his basement.

The film does a workaday job of laying the whole field out, and finishes admirably as well – a rare feat for a story that's still going on. Some very high profile problems like the hacking of the Mt Gox bitcoin exchange mean a lot of people (and the media) regard the movement as all but dead. But the value of a single bitcoin, which you can trade for more traditional currency like shares, was still in the stratosphere when the film was released, and bitcoins aren't the only digital currency around.

As the Mross brothers' film reminds us, genuine observers are interested in technologies that will change the world rather than just get rich quick investment opportunities look beyond the legal, political and monetary machinations. Mross and his contemporaries believe bitcoins have the capability to transform not just ecommerce but the very concept of money.

And if the internet's told us anything, it's to watch out for a world-changing idea even if the first iteration of it doesn't succeed. Classmates.com and Myspace.com came first, but Facebook got it right. The Facebook of digital currency might still be under development in some garage somewhere.