The process of probing and identifying security vulnerabilities and the extent to which they are used to a cracker’s advantage. It is a critical tool for assessing the security state of an organization’s IT systems, including computers, network components, and applications. Hackers of the White Hat variety are often hired by companies to do penetration testing. It is money well spent, computer security experts contend. Lowery, J. Penetration Testing: The Third Party Hacker. [Online, February, 2002.] Sans Institute Website. http://www.sans.org/rr/papers/index.php?id=264.