Question: what is trojan horse virus and its effects ? 

Answer: A program that either pretends to have, or is described as having, a set of useful or desirable features, but actually contains a damaging payload. Most frequently, the usage is shortened to "Trojan". Trojan Horses are not technically viruses, since they do not replicate.\n\nIn short, it's a program that seems innocent, but allows someone to be able to either transfer information or provide access to your computer, it can also transmit information
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