Basic Hacking Skills

The  Jargone file contains a bunch of definitions of the term ‘hacker’, most having to do with technical adeptness and a delight in solving problems and overcoming limits. If you want to know how to become a hacker, though, only two are really relevant.
There is a community, a shared culture, of expert programmers and networking wizards that traces its history back through decades to the first time-sharing minicomputers and the earliest ARPAnet experiments. The members of this culture originated the term ‘hacker’. Hackers built the Internet. Hackers made the Unix operating system what it is today. Hackers run Usenet. Hackers make the World Wide Web work. If you are part of this culture, if you have contributed to it and other people in it know who you are and call you a hacker, you're a hacker.
The hacker mind-set is not confined to this software-hacker culture. There are people who apply the hacker attitude to other things, like electronics or music — actually, you can find it at the highest levels of any science or art. Software hackers recognize these kindred spirits elsewhere and may call them ‘hackers’ too — and some claim that the hacker nature is really independent of the particular medium the hacker works in. But in the rest of this document we will focus on the skills and attitudes of software hackers, and the traditions of the shared culture that originated the term ‘hacker’.
There is another group of people who loudly call themselves hackers, but aren't. These are people (mainly adolescent males) who get a kick out of breaking into computers and phreaking the phone system. Real hackers call these people ‘crackers’ and want nothing to do with them. Real hackers mostly think crackers are lazy, irresponsible, and not very bright, and object that being able to break security doesn't make you a hacker any more than being able to hotwire cars makes you an automotive engineer. Unfortunately, many journalists and writers have been fooled into using the word ‘hacker’ to describe crackers; this irritates real hackers no end.
The basic difference is this: hackers build things, crackers break them
The hacker attitude is vital, but skills are even more vital. Attitude is no substitute for competence, and there's a certain basic toolkit of skills which you have to have before any hacker will dream of calling you one.
This toolkit changes slowly over time as technology creates new skills and makes old ones obsolete. For example, it used to include programming in machine language, and didn't until recently involve HTML. But right now it pretty clearly includes the following:

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Learn how to program.

This, of course, is the fundamental hacking skill. If you don't know any computer languages, I recommend starting with Python. It is cleanly designed, well documented, and relatively kind to beginners. Despite being a good first language, it is not just a toy; it is very powerful and flexible and well suited for large projects. I have written a more detailed evaluation of Python. Goodtutorials are available at the Python web site.
I used to recommend Java as a good language to learn early, but this critique has changed my mind (search for “The Pitfalls of Java as a First Programming Language” within it). A hacker cannot, as they devastatingly put it “approach problem-solving like a plumber in a hardware store”; you have to know what the components actually do. Now I think it is probably best to learn C and Lisp first, then Java.
There is perhaps a more general point here. If a language does too much for you, it may be simultaneously a good tool for production and a bad one for learning. It's not only languages that have this problem; web application frameworks like RubyOnRails, CakePHP, Django may make it too easy to reach a superficial sort of understanding that will leave you without resources when you have to tackle a hard problem, or even just debug the solution to an easy one.
If you get into serious programming, you will have to learn C, the core language of Unix. C++ is very closely related to C; if you know one, learning the other will not be difficult. Neither language is a good one to try learning as your first, however. And, actually, the more you can avoid programming in C the more productive you will be.
C is very efficient, and very sparing of your machine's resources. Unfortunately, C gets that efficiency by requiring you to do a lot of low-level management of resources (like memory) by hand. All that low-level code is complex and bug-prone, and will soak up huge amounts of your time on debugging. With today's machines as powerful as they are, this is usually a bad tradeoff — it's smarter to use a language that uses the machine's time less efficiently, but your time much more efficiently. Thus, Python.
Other languages of particular importance to hackers include Perl and LISP. Perl is worth learning for practical reasons; it's very widely used for active web pages and system administration, so that even if you never write Perl you should learn to read it. Many people use Perl in the way I suggest you should use Python, to avoid C programming on jobs that don't require C's machine efficiency. You will need to be able to understand their code.
LISP is worth learning for a different reason — the profound enlightenment experience you will have when you finally get it. That experience will make you a better programmer for the rest of your days, even if you never actually use LISP itself a lot. (You can get some beginning experience with LISP fairly easily by writing and modifying editing modes for the Emacs text editor, or Script-Fu plugins for the GIMP.)
It's best, actually, to learn all five of Python, C/C++, Java, Perl, and LISP. Besides being the most important hacking languages, they represent very different approaches to programming, and each will educate you in valuable ways.
But be aware that you won't reach the skill level of a hacker or even merely a programmer simply by accumulating languages — you need to learn how to think about programming problems in a general way, independent of any one language. To be a real hacker, you need to get to the point where you can learn a new language in days by relating what's in the manual to what you already know. This means you should learn several very different languages.
I can't give complete instructions on how to learn to program here — it's a complex skill. But I can tell you that books and courses won't do it — many, maybe most of the best hackers are self-taught. You can learn language features — bits of knowledge — from books, but the mind-set that makes that knowledge into living skill can be learned only by practice and apprenticeship. What will do it is (a) reading code and (b) writing code.
Peter Norvig, who is one of Google's top hackers and the co-author of the most widely used textbook on AI, has written an excellent essay called Teach Yourself Programming in Ten Years. His "recipe for programming success" is worth careful attention.
Learning to program is like learning to write good natural language. The best way to do it is to read some stuff written by masters of the form, write some things yourself, read a lot more, write a little more, read a lot more, write some more ... and repeat until your writing begins to develop the kind of strength and economy you see in your models.
Finding good code to read used to be hard, because there were few large programs available in source for fledgeling hackers to read and tinker with. This has changed dramatically; open-source software, programming tools, and operating systems (all built by hackers) are now widely available. Which brings me neatly to our next topic...

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Get one of the open-source Unixes and learn to use and run it.

I'll assume you have a personal computer or can get access to one. (Take a moment to appreciate how much that means. The hacker culture originally evolved back when computers were so expensive that individuals could not own them.) The single most important step any newbie can take toward acquiring hacker skills is to get a copy of Linux or one of the BSD-Unixes or OpenSolaris, install it on a personal machine, and run it.
Yes, there are other operating systems in the world besides Unix. But they're distributed in binary — you can't read the code, and you can't modify it. Trying to learn to hack on a Microsoft Windows machine or under any other closed-source system is like trying to learn to dance while wearing a body cast.
Under Mac OS X it's possible, but only part of the system is open source — you're likely to hit a lot of walls, and you have to be careful not to develop the bad habit of depending on Apple's proprietary code. If you concentrate on the Unix under the hood you can learn some useful things.
Unix is the operating system of the Internet. While you can learn to use the Internet without knowing Unix, you can't be an Internet hacker without understanding Unix. For this reason, the hacker culture today is pretty strongly Unix-centered. (This wasn't always true, and some old-time hackers still aren't happy about it, but the symbiosis between Unix and the Internet has become strong enough that even Microsoft's muscle doesn't seem able to seriously dent it.)
So, bring up a Unix — I like Linux myself but there are other ways (and yes, you can run both Linux and Microsoft Windows on the same machine). Learn it. Run it. Tinker with it. Talk to the Internet with it. Read the code. Modify the code. You'll get better programming tools (including C, LISP, Python, and Perl) than any Microsoft operating system can dream of hosting, you'll have fun, and you'll soak up more knowledge than you realize you're learning until you look back on it as a master hacker.
For more about learning Unix, see The Loginataka. You might also want to have a look at The Art Of Unix Programming.
To get your hands on a Linux, see the Linux Online! site; you can download from there or (better idea) find a local Linux user group to help you with installation.
During the first ten years of this HOWTO's life, I reported that from a new user's point of view, all Linux distributions are almost equivalent. But in 2006-2007, an actual best choice emerged: Ubuntu. While other distros have their own areas of strength, Ubuntu is far and away the most accessible to Linux newbies.
You can find BSD Unix help and resources at www.bsd.org.
A good way to dip your toes in the water is to boot up what Linux fans call a live CD, a distribution that runs entirely off a CD without having to modify your hard disk. This will be slow, because CDs are slow, but it's a way to get a look at the possibilities without having to do anything drastic.
I have written a primer on the basics of Unix and the Internet.
I used to recommend against installing either Linux or BSD as a solo project if you're a newbie. Nowadays the installers have gotten good enough that doing it entirely on your own is possible, even for a newbie. Nevertheless, I still recommend making contact with your local Linux user's group and asking for help. It can't hurt, and may smooth the process.

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Learn how to use the World Wide Web and write HTML.

Most of the things the hacker culture has built do their work out of sight, helping run factories and offices and universities without any obvious impact on how non-hackers live. The Web is the one big exception, the huge shiny hacker toy that evenpoliticians admit has changed the world. For this reason alone (and a lot of other good ones as well) you need to learn how to work the Web.
This doesn't just mean learning how to drive a browser (anyone can do that), but learning how to write HTML, the Web's markup language. If you don't know how to program, writing HTML will teach you some mental habits that will help you learn. So build a home page. Try to stick to XHTML, which is a cleaner language than classic HTML. (There are good beginner tutorials on the Web; here's one.)
But just having a home page isn't anywhere near good enough to make you a hacker. The Web is full of home pages. Most of them are pointless, zero-content sludge — very snazzy-looking sludge, mind you, but sludge all the same (for more on this seeThe HTML Hell Page).

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If you don't have functional English, learn it.

As an American and native English-speaker myself, I have previously been reluctant to suggest this, lest it be taken as a sort of cultural imperialism. But several native speakers of other languages have urged me to point out that English is the working language of the hacker culture and the Internet, and that you will need to know it to function in the hacker community.
Back around 1991 I learned that many hackers who have English as a second language use it in technical discussions even when they share a birth tongue; it was reported to me at the time that English has a richer technical vocabulary than any other language and is therefore simply a better tool for the job. For similar reasons, translations of technical books written in English are often unsatisfactory (when they get done at all).
Linus Torvalds, a Finn, comments his code in English (it apparently never occurred to him to do otherwise). His fluency in English has been an important factor in his ability to recruit a worldwide community of developers for Linux. It's an example worth following.
Being a native English-speaker does not guarantee that you have language skills good enough to function as a hacker. If your writing is semi-literate, ungrammatical, and riddled with misspellings, many hackers (including myself) will tend to ignore you. While sloppy writing does not invariably mean sloppy thinking, we've generally found the correlation to be strong — and we have no use for sloppy thinkers. If you can't yet write competently, learn to.

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Attitude is no substitute for competence.

To be a hacker, you have to develop some of these attitudes. But copping an attitude alone won't make you a hacker, any more than it will make you a champion athlete or a rock star. Becoming a hacker will take intelligence, practice, dedication, and hard work.
Therefore, you have to learn to distrust attitude and respect competence of every kind. Hackers won't let posers waste their time, but they worship competence — especially competence at hacking, but competence at anything is valued. Competence at demanding skills that few can master is especially good, and competence at demanding skills that involve mental acuteness, craft, and concentration is best.
If you revere competence, you'll enjoy developing it in yourself — the hard work and dedication will become a kind of intense play rather than drudgery. That attitude is vital to becoming a hacker.

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Freedom is good.

Hackers are naturally anti-authoritarian. Anyone who can give you orders can stop you from solving whatever problem you're being fascinated by — and, given the way authoritarian minds work, will generally find some appallingly stupid reason to do so. So the authoritarian attitude has to be fought wherever you find it, lest it smother you and other hackers.
(This isn't the same as fighting all authority. Children need to be guided and criminals restrained. A hacker may agree to accept some kinds of authority in order to get something he wants more than the time he spends following orders. But that's a limited, conscious bargain; the kind of personal surrender authoritarians want is not on offer.)
Authoritarians thrive on censorship and secrecy. And they distrust voluntary cooperation and information-sharing — they only like ‘cooperation’ that they control. So to behave like a hacker, you have to develop an instinctive hostility to censorship, secrecy, and the use of force or deception to compel responsible adults. And you have to be willing to act on that belief.

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Boredom and drudgery are evil.

Hackers (and creative people in general) should never be bored or have to drudge at stupid repetitive work, because when this happens it means they aren't doing what only they can do — solve new problems. This wastefulness hurts everybody. Therefore boredom and drudgery are not just unpleasant but actually evil.
To behave like a hacker, you have to believe this enough to want to automate away the boring bits as much as possible, not just for yourself but for everybody else (especially other hackers).
(There is one apparent exception to this. Hackers will sometimes do things that may seem repetitive or boring to an observer as a mind-clearing exercise, or in order to acquire a skill or have some particular kind of experience you can't have otherwise. But this is by choice — nobody who can think should ever be forced into a situation that bores them.)

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How do I tell if I am already a hacker?five principles of the hacker mindset

Ask yourself the following three questions ? YOU are hacker or NOT ?

• Do you speak code, fluently  ?
• Do you identify with the goals and values of the hacker community ?
• Has a well-established member of the hacker community ever called you a hacker?
  
  If you can answer yes to all three of these questions, you are already a hacker. No two alone are sufficient.
  
  The first test is about skills. You probably pass it if you have the minimum technical skills described earlier in this document. You blow right through it if you have had a substantial amount of code accepted by an open-source development project.

The second test is about attitude. If the 5 principels of the hacker mindset seemed obvious to you, more like a description of the way you already live than anything novel, you are already halfway to passing it. That's the inward half; the other, outward half is the degree to which you identify with the hacker community's long-term projects.
Here is an incomplete but indicative list of some of those projects: Does it matter to you that Linux improve and spread? Are you passionate about software freedom? Hostile to monopolies? Do you act on the belief that computers can be instruments of empowerment that make the world a richer and more humane place?
But a note of caution is in order here. The hacker community has some specific, primarily defensive political interests — two of them are defending free-speech rights and fending off "intellectual-property" power grabs that would make open source illegal. Some of those long-term projects are civil-liberties organizations like the Electronic Frontier Foundation, and the outward attitude properly includes support of them. But beyond that, most hackers view attempts to systematize the hacker attitude into an explicit political program with suspicion; we've learned, the hard way, that these attempts are divisive and distracting. If someone tries to recruit you to march on your capitol in the name of the hacker attitude, they've missed the point. The right response is probably “Shut up and show them the code.”
The third test has a tricky element of recursiveness about it. I observed in the section called “What Is a Hacker?” that being a hacker is partly a matter of belonging to a particular subculture or social network with a shared history, an inside and an outside. In the far past, hackers were a much less cohesive and self-aware group than they are today. But the importance of the social-network aspect has increased over the last thirty years as the Internet has made connections with the core of the hacker subculture easier to develop and maintain. One easy behavioral index of the change is that, in this century, we have our own T-shirts.
Sociologists, who study networks like those of the hacker culture under the general rubric of "invisible colleges", have noted that one characteristic of such networks is that they have gatekeepers — core members with the social authority to endorse new members into the network. Because the "invisible college" that is hacker culture is a loose and informal one, the role of gatekeeper is informal too. But one thing that all hackers understand in their bones is that not every hacker is a gatekeeper. Gatekeepers have to have a certain degree of seniority and accomplishment before they can bestow the title. How much is hard to quantify, but every hacker knows it when they see it.

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Will you teach me how to hack?

Since first publishing this page, I've gotten several requests a week (often several a day) from people to "teach me all about hacking". Unfortunately, I don't have the time or energy to do this; my own hacking projects, and working as an open-source advocate, take up 110% of my time.
Even if I did, hacking is an attitude and skill you basically have to teach yourself. You'll find that while real hackers want to help you, they won't respect you if you beg to be spoon-fed everything they know.
Learn a few things first. Show that you're trying, that you're capable of learning on your own. Then go to the hackers you meet with specific questions.
If you do email a hacker asking for advice, here are two things to know up front. First, we've found that people who are lazy or careless in their writing are usually too lazy and careless in their thinking to make good hackers — so take care to spell correctly, and use good grammar and punctuation, otherwise you'll probably be ignored. Secondly, don't dare ask for a reply to an ISP account that's different from the account you're sending from; we find people who do that are usually thieves using stolen accounts, and we have no interest in rewarding or assisting thievery.

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Ask yourself the following three questions ? YOU are hacker or NOT ?

• Do you speak code, fluently  ?
• Do you identify with the goals and values of the hacker community ?
• Has a well-established member of the hacker community ever called you a hacker?
  
  If you can answer yes to all three of these questions, you are already a hacker. No two alone are sufficient.
  
  The first test is about skills. You probably pass it if you have the minimum technical skills described earlier in this document. You blow right through it if you have had a substantial amount of code accepted by an open-source development project.

The second test is about attitude. If the 5 principels of the hacker mindset seemed obvious to you, more like a description of the way you already live than anything novel, you are already halfway to passing it. That's the inward half; the other, outward half is the degree to which you identify with the hacker community's long-term projects.

Here is an incomplete but indicative list of some of those projects: Does it matter to you that Linux improve and spread? Are you passionate about software freedom? Hostile to monopolies? Do you act on the belief that computers can be instruments of empowerment that make the world a richer and more humane place?

But a note of caution is in order here. The hacker community has some specific, primarily defensive political interests — two of them are defending free-speech rights and fending off "intellectual-property" power grabs that would make open source illegal. Some of those long-term projects are civil-liberties organizations like the Electronic Frontier Foundation, and the outward attitude properly includes support of them. But beyond that, most hackers view attempts to systematize the hacker attitude into an explicit political program with suspicion; we've learned, the hard way, that these attempts are divisive and distracting. If someone tries to recruit you to march on your capitol in the name of the hacker attitude, they've missed the point. The right response is probably “Shut up and show them the code.”

The third test has a tricky element of recursiveness about it. I observed in WHAT IS HACKER ? that being a hacker is partly a matter of belonging to a particular subculture or social network with a shared history, an inside and an outside. In the far past, hackers were a much less cohesive and self-aware group than they are today. But the importance of the social-network aspect has increased over the last thirty years as the Internet has made connections with the core of the hacker subculture easier to develop and maintain. One easy behavioral index of the change is that, in this century, we have our own T-shirts.

Sociologists, who study networks like those of the hacker culture under the general rubric of "invisible colleges", have noted that one characteristic of such networks is that they have gatekeepers — core members with the social authority to endorse new members into the network. Because the "invisible college" that is hacker culture is a loose and informal one, the role of gatekeeper is informal too. But one thing that all hackers understand in their bones is that not every hacker is a gatekeeper. Gatekeepers have to have a certain degree of seniority and accomplishment before they can bestow the title. How much is hard to quantify, but every hacker knows it when they see it.

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Serve the hacker culture itself

Finally, you can serve and propagate the culture itself (by, for example, writing an accurate primer on how to become a hacker :-)). This is not something you'll be positioned to do until you've been around for while and become well-known for one of the first four things.
The hacker culture doesn't have leaders, exactly, but it does have culture heroes and tribal elders and historians and spokespeople. When you've been in the trenches long enough, you may grow into one of these. Beware: hackers distrust blatant ego in their tribal elders, so visibly reaching for this kind of fame is dangerous. Rather than striving for it, you have to sort of position yourself so it drops in your lap, and then be modest and gracious about your status.

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Historical Note: Hacking, Open Source, and Free Software

hen I originally wrote this how-to in late 1996, some of the conditions around it were very different from the way they look today. A few words about these changes may help clarify matters for people who are confused about the relationship of open source, free software, and Linux to the hacker community. If you are not curious about this, you can skip straight to the FAQ and bibliography from here.
The hacker ethos and community as I have described it here long predates the emergence of Linux after 1990; I first became involved with it around 1976, and, its roots are readily traceable back to the early 1960s. But before Linux, most hacking was done on either proprietary operating systems or a handful of quasi-experimental homegrown systems like MIT's ITS that were never deployed outside of their original academic niches. While there had been some earlier (pre-Linux) attempts to change this situation, their impact was at best very marginal and confined to communities of dedicated true believers which were tiny minorities even within the hacker community, let alone with respect to the larger world of software in general.
What is now called "open source" goes back as far as the hacker community does, but until 1985 it was an unnamed folk practice rather than a conscious movement with theories and manifestos attached to it. This prehistory ended when, in 1985, arch-hacker Richard Stallman ("RMS") tried to give it a name — "free software". But his act of naming was also an act of claiming; he attached ideological baggage to the "free software" label which much of the existing hacker community never accepted. As a result, the "free software" label was loudly rejected by a substantial minority of the hacker community (especially among those associated with BSD Unix), and used with serious but silent reservations by a majority of the remainder (including myself).
Despite these reservations, RMS's claim to define and lead the hacker community under the "free software" banner broadly held until the mid-1990s. It was seriously challenged only by the rise of Linux. Linux gave open-source development a natural home. Many projects issued under terms we would now call open-source migrated from proprietary Unixes to Linux. The community around Linux grew explosively, becoming far larger and more heterogenous than the pre-Linux hacker culture. RMS determinedly attempted to co-opt all this activity into his "free software" movement, but was thwarted by both the exploding diversity of the Linux community and the public skepticism of its founder, Linus Torvalds. Torvalds continued to use the term "free software" for lack of any alternative, but publicly rejected RMS's ideological baggage. Many younger hackers followed suit.
In 1996, when I first published this Hacker HOWTO, the hacker community was rapidly reorganizing around Linux and a handful of other open-source operating systems (notably those descended from BSD Unix). Community memory of the fact that most of us had spent decades developing closed-source software on closed-source operating systems had not yet begun to fade, but that fact was already beginning to seem like part of a dead past; hackers were, increasingly, defining themselves as hackers by their attachments to open-source projects such as Linux or Apache.
The term "open source", however, had not yet emerged; it would not do so until early 1998. When it did, most of hacker community adopted it within the following six months; the exceptions were a minority ideologically attached to the term "free software". Since 1998, and especially after about 2003, the identification of 'hacking' with 'open-source (and free software) development' has become extremely close. Today there is little point in attempting to distinguish between these categories, and it seems unlikely that will change in the future.
It is worth remembering, however, that this was not always so.

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The world is full of fascinating problems waiting to be solved.

Being a hacker is lots of fun, but it's a kind of fun that takes lots of effort. The effort takes motivation. Successful athletes get their motivation from a kind of physical delight in making their bodies perform, in pushing themselves past their own physical limits. Similarly, to be a hacker you have to get a basic thrill from solving problems, sharpening your skills, and exercising your intelligence.
If you aren't the kind of person that feels this way naturally, you'll need to become one in order to make it as a hacker. Otherwise you'll find your hacking energy is sapped by distractions like sex, money, and social approval.
(You also have to develop a kind of faith in your own learning capacity — a belief that even though you may not know all of what you need to solve a problem, if you tackle just a piece of it and learn from that, you'll learn enough to solve the next piece — and so on, until you're done.)

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What is hacker ?

The  Jargone file contains a bunch of definitions of the term ‘hacker’, most having to do with technical adeptness and a delight in solving problems and overcoming limits. If you want to know how to become a hacker, though, only two are really relevant.
There is a community, a shared culture, of expert programmers and networking wizards that traces its history back through decades to the first time-sharing minicomputers and the earliest ARPAnet experiments. The members of this culture originated the term ‘hacker’. Hackers built the Internet. Hackers made the Unix operating system what it is today. Hackers run Usenet. Hackers make the World Wide Web work. If you are part of this culture, if you have contributed to it and other people in it know who you are and call you a hacker, you're a hacker.
The hacker mind-set is not confined to this software-hacker culture. There are people who apply the hacker attitude to other things, like electronics or music — actually, you can find it at the highest levels of any science or art. Software hackers recognize these kindred spirits elsewhere and may call them ‘hackers’ too — and some claim that the hacker nature is really independent of the particular medium the hacker works in. But in the rest of this document we will focus on the skills and attitudes of software hackers, and the traditions of the shared culture that originated the term ‘hacker’.
There is another group of people who loudly call themselves hackers, but aren't. These are people (mainly adolescent males) who get a kick out of breaking into computers and phreaking the phone system. Real hackers call these people ‘crackers’ and want nothing to do with them. Real hackers mostly think crackers are lazy, irresponsible, and not very bright, and object that being able to break security doesn't make you a hacker any more than being able to hotwire cars makes you an automotive engineer. Unfortunately, many journalists and writers have been fooled into using the word ‘hacker’ to describe crackers; this irritates real hackers no end.
The basic difference is this: hackers build things, crackers break them.

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