Wiretapping means secretly listening someone’s conversation over the phone. It’s done by using a spy bug. A bug is installed in a telephone and transmits all the phone conversations back to the spy. Not long ago cell phone tapping emerged as a new type of phone tapping. This time, no bugs are being used. It’s done with the help of software applications that can be installed remotely into someone’s cell phone.
Government agencies have been infamous for wiretapping citizens throughout the US history. It’s still a common practice today used to monitor terrorist suspects or whole organizations. While generally it is not legal to listen to someone’s phone conversations without permission, in some places there are no laws against it.