Sunday, March 4, 2007

The Hacker/Nerd Connection

Contrary to popular myth, you don't have to be a nerd to be a hacker. It does help, however, and many hackers are in fact nerds. Being something a social outcast helps you stay concentrated on the really important things, like thinking and hacking.

For this reason, many hackers have adopted the label ‘geek’ as a badge of pride — it's a way of declaring their independence from normal social expectations (as well as a fondness for other things like science fiction and strategy games that often go with being a hacker). The term 'nerd' used to be used this way back in the 1990s, back when 'nerd' was a mild pejorative and 'geek' a rather harsher one; sometime after 2000 they switched places, at least in U.S. popular culture, and there is now even a significant geek-pride culture among people who aren't techies.

If you can manage to concentrate enough on hacking to be good at it and still have a life, that's fine. This is a lot easier today than it was when I was a newbie in the 1970s; mainstream culture is much friendlier to techno-nerds now. There are even growing numbers of people who realize that hackers are often high-quality lover and spouse material.

If you're attracted to hacking because you don't have a life, that's OK too — at least you won't have trouble concentrating. Maybe you'll get a life later on.

Status in the Hacker Culture

Like most cultures without a money economy, hackerdom runs on reputation. You're trying to solve interesting problems, but how interesting they are, and whether your solutions are really good, is something that only your technical peers or superiors are normally equipped to judge.

Accordingly, when you play the hacker game, you learn to keep score primarily by what other hackers think of your skill (this is why you aren't really a hacker until other hackers consistently call you one). This fact is obscured by the image of hacking as solitary work; also by a hacker-cultural taboo (gradually decaying since the late 1990s but still potent) against admitting that ego or external validation are involved in one's motivation at all.

Specifically, hackerdom is what anthropologists call a gift culture. You gain status and reputation in it not by dominating other people, nor by being beautiful, nor by having things other people want, but rather by giving things away. Specifically, by giving away your time, your creativity, and the results of your skill.

There are basically five kinds of things you can do to be respected by hackers:

1. Write open-source software

The first (the most central and most traditional) is to write programs that other hackers think are fun or useful, and give the program sources away to the whole hacker culture to use.

(We used to call these works “free software”, but this confused too many people who weren't sure exactly what “free” was supposed to mean. Most of us now prefer the term “open-source” software).

Hackerdom's most revered demigods are people who have written large, capable programs that met a widespread need and given them away, so that now everyone uses them.

But there's a bit of a fine historical point here. While hackers have always looked up to the open-source developers among them as our community's hardest core, before the mid-1990s most hackers most of the time worked on closed source. This was still true when I wrote the first version of this HOWTO in 1996; it took the mainstreaming of open-source software after 1997 to change things. Today, "the hacker community" and "open-source developers" are two descriptions for what is essentially the same culture and population — but it is worth remembering that this was not always so.

2. Help test and debug open-source software

They also serve who stand and debug open-source software. In this imperfect world, we will inevitably spend most of our software development time in the debugging phase. That's why any open-source author who's thinking will tell you that good beta-testers (who know how to describe symptoms clearly, localize problems well, can tolerate bugs in a quickie release, and are willing to apply a few simple diagnostic routines) are worth their weight in rubies. Even one of these can make the difference between a debugging phase that's a protracted, exhausting nightmare and one that's merely a salutary nuisance.

If you're a newbie, try to find a program under development that you're interested in and be a good beta-tester. There's a natural progression from helping test programs to helping debug them to helping modify them. You'll learn a lot this way, and generate good karma with people who will help you later on.

3. Publish useful information

Another good thing is to collect and filter useful and interesting information into web pages or documents like Frequently Asked Questions (FAQ) lists, and make those generally available.

Maintainers of major technical FAQs get almost as much respect as open-source authors.
4. Help keep the infrastructure working

The hacker culture (and the engineering development of the Internet, for that matter) is run by volunteers. There's a lot of necessary but unglamorous work that needs done to keep it going — administering mailing lists, moderating newsgroups, maintaining large software archive sites, developing RFCs and other technical standards.

People who do this sort of thing well get a lot of respect, because everybody knows these jobs are huge time sinks and not as much fun as playing with code. Doing them shows dedication.

5. 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.




Basic Hacking Skills

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:

1. 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. Good tutorials are available at the Python web site.

Java is also a good language for learning to program in. It is more difficult than Python, but produces faster code than Python. I think it makes an excellent second language. Unfortunately, Sun's reference implementation is still proprietary. This is not so much an issue with the Java language itself, as high-quality open-source Java interpreters are readily available; the real problem is the class libraries that travel with the language. The open-source class libraries lag behind Sun's. So, if you do choose to learn Java, do it with one of the open-source implementations rather than becoming dependent on Sun's proprietary code.

But be aware that you won't reach the skill level of a hacker or even merely a programmer if you only know one or two 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.

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.

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...

2. 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. From a new user's point of view, all Linux distributions are pretty much equivalent.

You can find BSD Unix help and resources at www.bsd.org.

I have written a primer on the basics of Unix and the Internet.

(Note: I don't really recommend installing either Linux or BSD as a solo project if you're a newbie. For Linux, find a local Linux user's group and ask for help.)

3. 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 even politicians 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 see The HTML Hell Page).

To be worthwhile, your page must have content — it must be interesting and/or useful to other hackers. And that brings us to the next topic...

4. 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.

Thursday, March 1, 2007

Who Is Hacker

From Wikipedia, the free encyclopedia

A hacker is often someone who creates and modifies computer software or computer hardware, including computer programming, administration, and security-related items. A hacker is also someone who modifies electronics, for example, ham radio transceivers, printers or even home sprinkler systems to get extra functionality or performance. The term usually bears strong connotations, but may be either favorable or denigrating depending on cultural context (see the hacker definition controversy).
  • In computer programming, a hacker is a software designer and programmer who builds elegant, beautiful programs and systems. A hacker can also be a programmer who hacks or reaches a goal by employing a series of modifications to exploit or extend existing code or resources. For some, "hacker" has a negative connotation and refers to a person who "hacks" or uses kludges to accomplish programming tasks that are ugly, inelegant, and inefficient. This pejorative form of the noun "hack" is even used incorrectly among users of the positive sense of "hacker".
  • In computer security, a hacker is a person who specializes in work with the security mechanisms for computer and network systems. While including those who endeavor to strengthen such mechanisms, it is more often used by the mass media and popular culture to refer to those who seek access despite them.
  • In other technical fields, hacker is extended to mean a person who makes things work beyond perceived limits through their own technical skill, such as a hardware hacker, or reality hacker.
  • In hacker culture, a hacker is a person who has attained a certain social status and is recognized among members of the culture for commitment to the culture's values and a certain amount of technical knowledge.
Categories of hacker

The hacker community, the set of people who would describe themselves as hackers or described by others as hackers, falls into at least three partially overlapping categories. Sometimes alternate terms such as "cracker" are used in an attempt to more exactly distinguish which category of hacker is intended, or when attempting to put a contextual distance between the categories due to the hacker definition controversy.

Hacker: Highly skilled programmer

This mainly positive usage of hacker refers to one who knows a (sometimes specified) set of programming interfaces well enough to program rapidly and expertly. This type of hacker is well-respected (although the term still carries some of the meaning of hack), and is capable of developing programs without adequate planning or where pre-planning is difficult or impossible to achieve. This situation gives freedom and the ability to be creative against a methodical and careful progress. At their best, hackers can be very productive. The technical downside of hacker productivity is often 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 environments 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.

Additionally, there is sometimes a social downside associated with hacking. The stereotype of a hacker as having gained technical ability at a cost in social ability has been observed by many individuals, including noted psychologist Phillip Zimbardo[1]. Some researches have speculated on a possible link between hacking and conditions in the Autism spectrum, such as Asperger's Syndrome[2]; for example, Bram Cohen, the hacker who created the Bittorrent protocol, is believed by many (including himself) to have Asperger's[3]. While such social stunting from whatever cause is not universal among hackers, nor even only restricted to hackers, the difficulty in relating to others and the often abrasive personalities of some hackers makes some of them difficult to work with or to organize into teams.[4] On the other hand, it is not uncommon for hackers to thrive on social interaction.

Hacker: Computer and network security expert
Main article: Hacker (computer security)

In the networking sense, a hacker is one who specializes in work with the access control mechanisms for computer and network systems. This includes individuals who work toward maintaining and improving the integrity of such mechanisms. However, the most common usage of hacker in this respect refers to someone who exploits systems or gains unauthorized access by means of clever tactics and detailed knowledge, while taking advantage of any carelessness or ignorance on the part of system operators. This use of hacker as intruder (frequent in the media) generally has a strong negative connotation, and is disparaged and discouraged within the computer community, resulting in the modern Hacker definition controversy.

For such hackers specializing in intrusion, the highly derogatory term script kiddies is often used to indicate those who either claim to have far more skill than they actually have, or who exclusively use programs developed by others to achieve a successful security exploit.

Hacker: Hardware modifier
Main article: Hardware hacker
A modified computer, featuring water cooling and ultraviolet lighting

Another type of hacker is one who creates novel hardware modifications. At the most basic end of this spectrum are those who make frequent changes to the hardware in their computers using standard components, or make semi-cosmetic themed modifications to the appearance of the machine. This type of Hacker modifies his/her computer for performance needs and/or aesthetics. These changes often include adding memory, storage or LEDs and cold cathode tubes for light effects. These people often show off their talents in contests, and many enjoy LAN parties. At the more advanced end of the hardware hackers are those who modify hardware (not limited to computers) to expand capabilities; this group blurs into the culture of hobbyist inventors and professional electronics engineering. An example of such modification includes the addition of TCP/IP Internet capabilities to a number of vending machines and coffee makers during the late 1980s and early 1990s.

Hackers who have the ability to write circuit-level code, device drivers, firmware, low-level networking, (and even more impressively, using these techniques to make devices do things outside of their spec sheets), are typically in very high regard among hacker communities. This is primarily due to the enormous difficulty, complexity and specialized domain knowledge required for this type of work, as well as the electrical engineering expertise that plays a large role. Such hackers are rare, and almost always considered to be wizards or gurus of a very high degree.