When one tries to break into or use a computer system wrongly, he or she is considered an intruder. ‘Using wrongly’ is not a restricted term and can be used to represent an act of stealing confidential information or a minor offense of just misusing one’s email for the spam (Zachary, 2006). Presently, more people both through the internet and corporate intranets are continuously attempting to test the various systems’ security. The motive differs in every instance but revenge and stealing for profit are some of the motives driving intruders. ‘Hacker’ and ‘attacker’ are the two terms that are used in describing a person who tries to get into networks and systems.