A keylogger is a form of spyware that records what you type on your computer. It can capture information such as account names and passwords, credit card numbers, emails, instant messages, and more.
Keyloggers can be installed directly onto a user’s computer or through an email attachment or malicious website link. Once installed, the software usually starts up automatically whenever the user logs into Windows or opens a browser window with Internet Explorer or Firefox. The keylogger then starts recording everything that is typed on the keyboard including usernames, passwords, and other confidential information.