Trojan horse
not spread by itself. However, the Trojan can be a module of the virus.
Trojans differ among themselves on those activities that they produce on the infected computer.
Backdoor - Trojan remote administration utility
Utility hidden controls allow you to do with the computer all that they laid the author: to take or
send files, start and destroy them, display messages, erase, reboot the computer, etc.
Trojan-PSW - stealing passwords
When you start looking for PSW-Trojan sictemnye files stored on a range of confidential
information (usually phone numbers and passwords to access the Internet) and send it to the
specified code in the "Trojan" e-mail address or addresses.
Trojan-Clicker - Internet clickers.
This family of Trojans, whose main function - the organization of unauthorized access to Internet
resources.
Trojan-Downloader - Ships other malware
Trojan horses of this class are designed to download and install on the victim machine new versions of
annaabi.ee 
