I have blu-ray. The acquisition of a new generation of storage has, in the past, prompted excited realisation of the power this gives me. The blue laser variant of optical storage comes as online storage, cloud computing, a supermassive hard drives threaten to outshine its glamour. But let's welcome this new gadget anyway.
In doing so, it's time once again to chart the transition of information from a kind of commodity to a kind of natural resource. It used to be coal, now it's air. How thick and heavy is coal and how light is air? Let's revisit some numbers.
I like to think of the audio CD as a standard for data... one album's worth of music, around 700 megabytes. CD-R and compression meant you could actually fit ten albums on that medium. DVD took it up to 4,700...you can get 80 albums on one of them. Double layer DVD made it about 9,000, (160 albums) although for the most part I only used single layer discs. Blu-ray double layer is 50 GB, more than 10 times my previous main medium (OK, I admit I'm spinning it a bit here as I will probably only afford single layer discs for a while, but for the sake of the exercise let's say we're going for DL discs). That's 1,600 albums on a single disc, of identical dimensions to that one album on the old school CD-R.