Key loggers

Key loggers:- 

A key logger is a tool designed to record ('log') every keystroke on an affected machine for 

later retrieval. Its purpose is usually to allow the user of this tool to gain access to confidential 

information typed on the affected machine, such as a user's password or other 

private data. Some key loggers uses virus-, trojan-, and rootkit-like methods to 

remain active and hidden. However, some key loggers are used in legitimate ways 

and 

sometimes to even enhance computer security. As an example, a business might have a 

key logger on a computer used at a point of sale and data collected by the key logger 

could be used for catching employee fraud.