Online and mobile technologies are facilitating the accumulation of vast amounts of data across business, industry, government and other areas of human endeavour. We have become dependent on the internet as a source of information for most of what we need to know, for access to entertainment, for communication with others, for purchases and banking and for carrying out our work. As our lives become increasingly intertwined with technology, we are generating huge quantities of ‘digital exhaust’ through the use of internet-connected extensions of ourselves: devices such as smartphones, tablets, laptops, e-book readers and fitness trackers.