Even if you have anti-virus system and fire wall you still are not safe! Trojans could be recording all your valuable passwords, credit cards etc. without you knowing it. A Trojan is a mini program running on a workstation (PC or Macintosh). It is a tool to control and supervise a computer. At its basic level, it merely records every key pressed together with the username and password when you access any computer network. Thus, it may give hackers chances of entering your computer and damaging the system.
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