What is the most common type of trojan horse?

What is the most common type of trojan horse?

In computer system security, a virus is a type of malicious code or program that self-replicates by inserting its code into other programs.  https://publicpush.de/?p=1363 As a result, contaminated computers can spread out the virus to other computer systems. advicehttps://islamhood.org/?p=652