The best protection is to get a program that protects against spyware. But be careful, many websites that claim to have them are actually spyware, not something to protect against it. This method of installing spyware is called a Trojan horse which is disguised as something useful but when it runs, its keystroke logging sees what keys you press. This makes it easy for the trojan operator to collect your passwords and important data and log into your accounts. Spyware tracks your computer and uses some of the things on it. This includes your files, your downloads, and usernames/passwords for websites and programs