Hacker

In the computer security context, a hacker is someone who seeks and exploits weaknesses in a computer system or computer network. Hackers may be motivated by a multitude of reasons, such as profit, protest, challenge or enjoyment. The subculture that has evolved around hackers is often referred to as the computer underground and is now a known community. While other uses of the word hacker exist that are related to computer security, such as referring to someone with an advanced understanding of computers and computer networks, they are rarely used in mainstream context. They are subject to the longstanding hacker definition controversy about the term's true meaning. In this controversy, the term hacker is reclaimed by computer programmers who argue that someone who breaks into computers, whether computer criminal (black hats) or computer security expert (white hats), is more appropriately called a cracker instead. Some white hat hackers claim that they also deserve the title hacker, and that only black hats should be called "crackers".

Several subgroups of the computer underground with different attitudes use different terms to demarcate themselves from each other, or try to exclude some specific group with whom they do not agree.

Eric S. Raymond, author of The New Hacker's Dictionary, advocates that members of the computer underground should be called crackers. Yet, those people see themselves as hackers and even try to include the views of Raymond in what they see as a wider hacker culture, a view that Raymond has harshly rejected. Instead of a hacker/cracker dichotomy, they emphasize a spectrum of different categories, such as white hat, grey hat, black hat and script kiddie. In contrast to Raymond, they usually reserve the term cracker for more malicious activity.

According to Ralph D. Clifford, a cracker or cracking is to "gain unauthorized access to a computer in order to commit another crime such as destroying information contained in that system". These subgroups may also be defined by the legal status of their activities.

Bruce Sterling traces part of the roots of the computer underground to the Yippies, a 1960s counterculture movement that published the Technological Assistance Program (TAP) newsletter.TAP was a phone phreaking newsletter that taught techniques for unauthorized exploration of the telephone network. Many people from the phreaking community are also active in the hacking community even today, and vice versa