Key logger
Also known as a keystroke logger, a keylogger is a software program or hardware device that is used to monitor and log each of the keys a user types into a computer keyboard. The user who installed the program or hardware device can then view all keys typed in by that user. Because these programs and hardware devices monitor the keys typed in, a user can easily find user passwords and other information a user may not wish others to know about.
Additionally, users who are using a hardware device and have access to a computer can easily connect these devices to the back of a computer, often without a user knowing about them, and then disconnect the device and connect it to another computer to obtain all the information.
Users who are concerned about their privacy or have sensitive data may wish to consider anti-keylogger protection software that is designed to prevent and stop hardware and software keyloggers.