Big Data is the big idea of the moment. According to IBM, we’re creating 2.5 quintillion bytes of data every day, with over 90% of the world’s data having been produced in the past two years alone. The data itself is everything from the songs you’ve been listening to and your holiday snaps to your medical records and the websites you’ve visited. Its applications are numerous and varied – from delivering personalised adverts to your computer to the perhaps more noble goal of predicting and dealing with epidemics.

Many hope these huge data sets will change our lives for the better. Combining vast data collection with computing power enables new research techniques to find links between environment, behaviour and illness, resulting in better health for us all. Linking health records to supermarket loyalty cards, for example, could allow the state to better target healthcare to individual needs, and provide a new intervention tool to change unhealthy behaviour. However this means giving up an element of the confidentiality we traditionally entrusted to our doctors - the new General Practice Extraction Service will remove identifiable patient data directly from GP records without consulting them, so it can be passed around and made available to researchers. It’s impossible to predict how, or by whom, information on us might be used in future. There are concerns too about the corporations who are collecting reams of information about us. ISPs, Google, Apple and network providers all collect information about their customers, and use it to their benefit. Governments too are interested in the data collected by these companies. With smart phones being ubiquitous, and the rise of technologies like Google Glass, our every moment can be recorded in some fashion and there are concerns that this all-encompassing surveillance has dire implications for our privacy.

Are we right to be worried about the privacy implications, or do we need to let go of some of our data for the greater good? Should we be asked for our consent every time our information is stored, as we are when we donate blood? Ought we to draw a line between data collection for use by scientists and policy purposes and the data collected by companies? Can big data change the world and if so, who do we trust with ours?