We are in the throes of a revolution, yet the rapid pace of technological and cultural change makes it difficult to understand what's going on. 50 Ideas You Really Need to Know: Digital provides a clear path through the misinformation surrounding those technologies that are transforming the world. Leading technology writer Tom Chatfield provides a sure-footed guide to the seminal digital phenomena of our time: from the basic browsers that we use to surf the web, to the implications for our own privacy. From plumbing the depths of the deep web that represents well over 99 per cent of the internet and remains inaccessible to most search engines, to digital distribution that threatens to sweep away entire industries, this is an indispensable road map for our journey to a digital future.