Is a program that disguises itself as an interesting, useful, or desirable program in order to gain access to your system

Trojan Horse

Explanation:

Trojan Horse is a program that disguises itself as an interesting, useful or desirable program in order to gain access to your system.

Trojan Horse is a malicious program downloaded virus which seems harmless to a computer but in reality it harms and modifies many activities of a computer. These activities may be unusual and they can also occur even when the computer is idle.

It seems like a genuine file or applications to trick you, once opened it deceives you by loading malware and make it execute on to the Operating system.

Trojan can make you fool by presenting itself like an email from a known source, but it never is. Some common types of Trojan malware are as follows: