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A hacker is anyone who enjoys the intellectual challenge of creatively overcoming or circumventing limitations, primarily in their fields of interest, namely programming or electrical engineering. As will be discussed below, there is a trend in the popular press to use the term to describe computer criminals, and others, whose motivations are less pure than the traditional hacker. This trend greatly annoys many of those old-school computer/technology enthusiasts.

Table of contents
1 Origin of the term at MIT
2 Hacker -- Brilliant Programmer
3 Hacker -- Computer Criminal
4 Hacker -- Grey Hat
5 Hacker -- White Hat
6 How Some Hackers Define Themselves
7 Notable Hackers
8 Notable Crackers
9 See also
10 External Links
11 Other meanings of the word "hacker"

Origin of the term at MIT

The term originally developed at MIT long before computers became common; a "hack" meant a simple, but often inelegant, solution. The term hack came to refer to any clever prank perpetrated by MIT students; the perpetrator is a hacker. To this day the terms hack and hacker are used in that way at MIT, without necessarily referring to computers. When MIT students surreptiously put a police car atop the dome on MIT's Building 10, that was a hack, and the students involved were therefore hackers.

Computer culture at MIT developed when members of the Tech Model Railroad Club started working with a Digital Equipment Corporation PDP-1 computer and applied local model railroad slang to computers. In modern computer culture, the label "hacker" is a compliment, indicating a skilled and clever programmer. In the media, however, it has negative connotations and has become synonymous with "software cracker".

The term hacker has five meanings that are in common usage:

  1. Someone who knows a (sometimes specified) set of programming interfaces well enough to write novel and useful software without conscious thought on a good day.
  2. Someone who (usually illegally) attempts to break into or otherwise subvert the security of a program, system or network, often with malicious intent. This usage was annoying to many in the developer community who grew up with the primary meaning in sense (1), and preferred to keep it that way; they preferred the media used the term cracker. However this wound up causing even more problems as simply creating a new word did nothing to dispel misconceptions. "Black hat hacker" is a phrase that wound up with the same problems as the word "cracker".
  3. Someone who attempts to break into systems or networks in order to help the owners of the system by making them aware of security flaws in it. This is referred to by some as a "white hat hacker" or sneaker. Many of these people are employed by computer security companies, and are doing something completely legal; and many were formerly hackers within sense 2.
  4. Someone who, through either knowledge or trial and error, makes a modification to an existing piece of software, made available to the hacker community, such that it provides a change of functionality. Such change is normally a benefit. Rather than a competition, the exchange of improvements is most often experienced as a cooperative learning effort.
  5. A Reality Hacker or Urban Spelunker (origin: MIT); someone who enjoys exploring air ducts, rooftops, shafts and other hidden aspects of urban life, sometimes including pulling elaborate pranks for the enjoyment and entertainment of the community.

"Script kiddie" is reserved for a computer user of little or no skill who simply follows directions or uses a cook-book approach without fully understanding the meaning of the steps they are performing.

"h4x0r" (pronounced Hacks-Or) is a script kiddie in the context of a computer game (i.e. someone who uses a program to modify a game giving them special and unfair advantages). "h4x0r" is often used jokingly or as a term of endearment between gamers.

Note that while the term hacker denotes competence, the noun hack often means kludge and thus has a negative connotation while the verb hack generally shares the same competent connotations.

See also jargon file.

The hacker community (the set of people who would describe themselves as hackers, or who would be described by others as hackers) falls into at least three partially overlapping categories. The word hacker probably derives from the somewhat derogatory hack, used in the newspaper industry typically to refer to a Journalist who types his stories without checking his facts first.

Hacker -- Brilliant Programmer

One who knows a (sometimes specified) set of programming interfaces well enough to write novel and useful software without conscious thought on a good day. This type of hacker is respected within the development community for the freedom they represent, although the term still carries some of the meaning of Hack, developing programs without adequate planning. This zugzwang sets freedom and the ability to be creative against methodical careful progress. Corporate programming environments typically favor only either the good hackers or the careful computer scientist.

At their best, Hackers can be surprisingly productive. Industry standard rates of development are in the range of 6-10 lines of code (debugged, and documented) per hour. A Hacker in stride can produce a few hundred or occasionally even thousands lines of code an hour by leveraging their previous work. As a result a Hacker may be able to sketch out the full shape of a program to a level of quality that can be used for demonstrating ideas in less than a week. Thus it isn't hard to see what some companies find useful in Hacker talent.

The down side of Hacker productivity is generally agreed to be in maintainability, documentation, and completion. Very talented hackers may become bored with a project once they have figured out all of the hard parts, and be unwilling to finish off the details. This attitude can cause friction in shops where other programmers are expected to pick up the half finished work, decipher the structures and ideas, and bullet-proof the code. In other cases, where a Hacker is willing to maintain their own code, a company may be unable to find anyone else who is capable or willing to dig through code to maintain the program if the original programmer moves on to a new job.

Hacker -- Computer Criminal

The popular press has been known to use the terms "hacker" and occasionally "cracker" for someone who attempts to break into or otherwise subvert the security of a system or network. Both usages are annoying to many in the developer community who grew up with the primary meaning of "hacker" in the Guru sense, and who don't see the problem solved by the invention of new and nebulous words like "cracker" or "black hat". Instead, there has been a move to define terms when describing these people. What makes someone a "hacker", a "computer criminal", or just a regular computer user? Once these details are known, the proper word (or combination) can be accurately applied.

While it will always be possible to use one's "hacker" skills in a destructive way, this tends to go against the loosely defined hacker ethic. One can certainly use hacking skills to commit a crime. However, this means that this particular hacker is now a criminal, vandal, malicious user, etc., existing words that do a much better job of describing the person's actions than the nebulous "cracker". If a locksmith used his skills to break into a building, few would debate that he had crossed into the criminal world and there would be no need to invent a word to define criminal or malicious locksmiths. The reason hackers face these kinds of problems is because the mass media tends to believe anyone who says they are a hacker - and people say they are hackers because of the mass media's sensationalist portrayals. This deceptive cycle will probably only come to an end with the education of reporters and the general public on what constitutes a hacker and what does not. A group known as the "Hacker Antidefamation League" has this goal.

But, indeed, it's likely that the confusion and dissonance exists precisely because "hacking" describes a *skill set* -- akin to picking locks -- whose tools can be used both ethically and unethically, by both people who are basically ethical, and those who are not (these are two related, but separate distinctions -- what long-time system administrator has not violated a company policy by breaking into some company facility for an authorized user in order that that person can complete an important project?) This may well be the crux of the argument, in fact: so-called 'white-hat' hackers are uncomfortable at the exposure of the darker side of their skill-set, notwithstanding the fact that, like comic-book superheroes, they only utilize those skills for Good.

Software cracking is the process of removing any sort of software enforced protection scheme from a piece of software.

There are several recurring tools of the trade used by hackers to gain unauthorized access to computers:

Hacker -- Grey Hat

1) A black-hat hacker turned white-hat. See below.

2) A white-hat hacker who uses black-hat techniques to satisfy their employers, for whom they act as white-hat.

Hacker -- White Hat

White hat hackers often overlap with black hat depending on your perspective. The primary difference is that a white hat hacker observes the hacker ethic, a sort of golden rule of computing similar to: Do unto others as you would have them do unto you. Like black hats, white hats are often intimately familiar with the internal details of security systems, and can delve into obscure machine code when needed to find a solution to a tricky problem without requiring support from a system manufacturer.

An example of a hack: Microsoft Windows ships with the ability to use cryptographic libraries built into the operating system. When shipped overseas this feature becomes nearly useless as the operating system will refuse to load cryptographic libraries that haven't been signed by Microsoft, and Microsoft will not sign a library unless the US Government authorizes it for export. This allows the US Government to maintain some perceived level of control over the use of strong cryptography beyond its borders.

While hunting through the symbol table of a beta release of Windows, a couple of overseas hackers managed to find a second signing key in the Microsoft binaries. That is without disabling the libraries that are included with Windows (even overseas) these individuals learned of a way to trick the operating system into loading a library that hadn't been signed by Microsoft, thus enabling the functionality which had been lost to non-US users.

Whether this is good (white hat) or bad (black hat) may depend on whether you are the US Government or not, but is generally considered by the computing community to be a white hat type of activity.

How Some Hackers Define Themselves

The following is the definition given by the jargon file (a dictionary of hacker jargon) accepted by some (but not all) in the hacker community:
hacker n.

[originally, someone who makes furniture with an axe]

  1. A person who enjoys exploring the details of programmable systems and how to stretch their capabilities, as opposed to most users, who prefer to learn only the minimum necessary.
  2. One who programs enthusiastically (even obsessively) or who enjoys programming rather than just theorizing about programming.
  3. A person capable of appreciating hack value.
  4. A person who is good at programming quickly.
  5. An expert at a particular program, or one who frequently does work using it or on it; as in `a Unix hacker'. (Definitions 1 through 5 are correlated, and people who fit them congregate.)
  6. An expert or enthusiast of any kind. One might be an astronomy hacker, for example.
  7. One who enjoys the intellectual challenge of creatively overcoming or circumventing limitations.
  8. [deprecated] A malicious meddler who tries to discover sensitive information by poking around. Hence `password hacker', `network hacker'. The correct term for this sense is cracker.

The term `hacker' also tends to connote membership in the global community defined by the net (see the network and Internet address). For discussion of some of the basics of this culture, see the How To Become A Hacker FAQ. It also implies that the person described is seen to subscribe to some version of the hacker ethic.

It is better to be described as a hacker by others than to describe oneself that way. Hackers consider themselves something of an elite (a meritocracy based on ability), though one to which new members are gladly welcome. There is thus a certain ego satisfaction to be had in identifying yourself as a hacker (but if you claim to be one and are not, you'll quickly be labeled bogus). See also geek, wannabee.

This term seems to have been first adopted as a badge in the 1960s by the hacker culture surrounding TMRC and the MIT AI Lab. We have a report that it was used in a sense close to this entry's by teenage radio hams and electronics tinkerers in the mid-1950s.

Notable Hackers

Notable Crackers

Here are a few of the more famous
crackers (many of whom have since turned to positive hacking):

See also

External Links

Other meanings of the word "hacker"

Hacker and Hack are also: terms for a taxicab driver (because a taxicab can be called a hack, a shortened form of hackney carriage).

Hacker, in golf, means a duffer, a mediocre player who enjoys playing but makes no serious effort to improve his skill.