Whether you move to more open systems on your PC and mobile devices or not, you need to take more care in protecting yourself in the digital sphere. This chapter is about fundamental steps we all can take to keep our data secure and prevent prying eyes from following our every move, while recognizing that this may well be impossible or, at best, impractical. We’ll discuss browser tools, encryption and a variety of other safeguards that work on all kinds of operating systems. We’ll also look at the pros and cons of using social networks such as Facebook, Google+ and Twitter – increasingly becoming a center of speech and collaboration but owned by private interests – and see if there are any useful alternatives to them.

Sidebar: Bruce Schneier, security expert.

Sidebar: A Syrian activist on the lethal risks of insecure communications.