A keylogger is a hardware device or a software program that records the real time activity of a computer user including the keyboard keys they press.
Keyloggers are used in IT organizations to troubleshoot technical problems with computers and business networks. Keyloggers can also be used by a family (or business) to monitor the network usage of people without their direct knowledge. Finally, malicious individuals may use keyloggers on public computers to steal passwords or credit card information.
Keylogger software is freely available on the Internet. These keyloggers allow not only keyboard keystrokes to be captured but also are often capable of collecting screen captures from the computer. Normal keylogging programs store their data on the local hard drive, but some are programmed to automatically transmit data over the network to a remote computer or Web server.
Detecting the presence of a keylogger on a computer can be difficult.
So-called anti-keylogging programs have been developed to thwart keylogging systems, and these are often effective when used properly.