A group of researchers studied 15 months of human mobility movement data taken from 1.5 million people and concluded that just four points in space and time were sufficient to identify 95 per cent of them, even when the data weren't of excellent quality. That was back in 2013. Nearly 10 years on, surveillance technologies permeate all aspects of our lives. They collect swathes of data from us in various forms, and often without us knowing. I'm a surveillance researcher with a focus on technology