In the era of total digitalization, it is difficult to imagine your life without the Internet and smart devices. But even people who act cautiously in the real world often aren't careful enough about their digital security. Meanwhile, the consequences of such carelessness can be encountered at any time: an attacker can take over control of a car, and the TV can record viewers’ conversations, criminals can use toys to kidnap children, and video cameras can be connected to and spy on the owners. There are also government projects like the “Smart City”, which involve the widespread introduction of video cameras and facial recognition technologies. All this does not mean that you need to strive for digital seclusion and panic avoid gadgets, but it is necessary to study and follow basic safety rules. Mikhail Reitman in his book tells how to minimize the likelihood of personal data leakage, making the task more difficult for potential attackers.