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+=head1 NAME
+
+perlfaq1 - General Questions About Perl
+
+=head1 DESCRIPTION
+
+This section of the FAQ answers very general, high-level questions
+about Perl.
+
+=head2 What is Perl?
+
+Perl is a high-level programming language with an eclectic heritage
+written by Larry Wall and a cast of thousands. It derives from the
+ubiquitous C programming language and to a lesser extent from sed,
+awk, the Unix shell, and at least a dozen other tools and languages.
+Perl's process, file, and text manipulation facilities make it
+particularly well-suited for tasks involving quick prototyping, system
+utilities, software tools, system management tasks, database access,
+graphical programming, networking, and world wide web programming.
+These strengths make it especially popular with system administrators
+and CGI script authors, but mathematicians, geneticists, journalists,
+and even managers also use Perl. Maybe you should, too.
+
+=head2 Who supports Perl? Who develops it? Why is it free?
+
+The original culture of the pre-populist Internet and the deeply-held
+beliefs of Perl's author, Larry Wall, gave rise to the free and open
+distribution policy of perl. Perl is supported by its users. The
+core, the standard Perl library, the optional modules, and the
+documentation you're reading now were all written by volunteers. See
+the personal note at the end of the README file in the perl source
+distribution for more details. See L<perlhist> (new as of 5.005)
+for Perl's milestone releases.
+
+In particular, the core development team (known as the Perl Porters)
+are a rag-tag band of highly altruistic individuals committed to
+producing better software for free than you could hope to purchase for
+money. You may snoop on pending developments via the archives at
+http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/
+and http://archive.develooper.com/perl5-porters@perl.org/
+or the news gateway nntp://nntp.perl.org/perl.perl5.porters or
+its web interface at http://nntp.perl.org/group/perl.perl5.porters ,
+or read the faq at http://dev.perl.org/perl5/docs/p5p-faq.html ,
+or you can subscribe to the mailing list by sending
+perl5-porters-subscribe@perl.org a subscription request
+(an empty message with no subject is fine).
+
+While the GNU project includes Perl in its distributions, there's no
+such thing as "GNU Perl". Perl is not produced nor maintained by the
+Free Software Foundation. Perl's licensing terms are also more open
+than GNU software's tend to be.
+
+You can get commercial support of Perl if you wish, although for most
+users the informal support will more than suffice. See the answer to
+"Where can I buy a commercial version of perl?" for more information.
+
+=head2 Which version of Perl should I use?
+
+(contributed by brian d foy)
+
+There is often a matter of opinion and taste, and there isn't any one
+answer that fits everyone. In general, you want to use either the current
+stable release, or the stable release immediately prior to that one.
+Currently, those are perl5.10.x and perl5.8.x, respectively.
+
+Beyond that, you have to consider several things and decide which is best
+for you.
+
+=over 4
+
+=item *
+
+If things aren't broken, upgrading perl may break them (or at least issue
+new warnings).
+
+=item *
+
+The latest versions of perl have more bug fixes.
+
+=item *
+
+The Perl community is geared toward supporting the most recent releases,
+so you'll have an easier time finding help for those.
+
+=item *
+
+Versions prior to perl5.004 had serious security problems with buffer
+overflows, and in some cases have CERT advisories (for instance,
+http://www.cert.org/advisories/CA-1997-17.html ).
+
+=item *
+
+The latest versions are probably the least deployed and widely tested, so
+you may want to wait a few months after their release and see what
+problems others have if you are risk averse.
+
+=item *
+
+The immediate, previous releases (i.e. perl5.8.x ) are usually maintained
+for a while, although not at the same level as the current releases.
+
+=item *
+
+No one is actively supporting Perl 4. Five years ago it was a dead
+camel carcass (according to this document). Now it's barely a skeleton
+as its whitewashed bones have fractured or eroded.
+
+=item *
+
+There is no Perl 6 release scheduled, but it will be available when
+it's ready. Stay tuned, but don't worry that you'll have to change
+major versions of Perl; no one is going to take Perl 5 away from you.
+
+=item *
+
+There are really two tracks of perl development: a maintenance version
+and an experimental version. The maintenance versions are stable, and
+have an even number as the minor release (i.e. perl5.10.x, where 10 is the
+minor release). The experimental versions may include features that
+don't make it into the stable versions, and have an odd number as the
+minor release (i.e. perl5.9.x, where 9 is the minor release).
+
+=back
+
+
+=head2 What are Perl 4, Perl 5, or Perl 6?
+
+(contributed by brian d foy)
+
+In short, Perl 4 is the past, Perl 5 is the present, and Perl 6 is the
+future.
+
+The number after perl (i.e. the 5 after Perl 5) is the major release
+of the perl interpreter as well as the version of the language. Each
+major version has significant differences that earlier versions cannot
+support.
+
+The current major release of Perl is Perl 5, and was released in 1994.
+It can run scripts from the previous major release, Perl 4 (March 1991),
+but has significant differences. It introduced the concept of references,
+complex data structures, and modules. The Perl 5 interpreter was a
+complete re-write of the previous perl sources.
+
+Perl 6 is the next major version of Perl, but it's still in development
+in both its syntax and design. The work started in 2002 and is still
+ongoing. Many of the most interesting features have shown up in the
+latest versions of Perl 5, and some Perl 5 modules allow you to use some
+Perl 6 syntax in your programs. You can learn more about Perl 6 at
+http://dev.perl.org/perl6/ .
+
+See L<perlhist> for a history of Perl revisions.
+
+=head2 What was Ponie?
+
+(contributed by brian d foy)
+
+Ponie stands for "Perl On the New Internal Engine", started by Arthur
+Bergman from Fotango in 2003, and subsequently run as a project of The
+Perl Foundation. It was abandoned in 2006
+( http://www.nntp.perl.org/group/perl.ponie.dev/487 ).
+
+Instead of using the current Perl internals, Ponie aimed to create a
+new one that would provide a translation path from Perl 5 to Perl 6
+(or anything else that targets Parrot, actually). You would have been
+able to just keep using Perl 5 with Parrot, the virtual machine which
+will compile and run Perl 6 bytecode.
+
+=head2 What is Perl 6?
+
+At The Second O'Reilly Open Source Software Convention, Larry Wall
+announced Perl 6 development would begin in earnest. Perl 6 was an oft
+used term for Chip Salzenberg's project to rewrite Perl in C++ named
+Topaz. However, Topaz provided valuable insights to the next version
+of Perl and its implementation, but was ultimately abandoned.
+
+If you want to learn more about Perl 6, or have a desire to help in
+the crusade to make Perl a better place then read the Perl 6 developers
+page at http://dev.perl.org/perl6/ and get involved.
+
+Perl 6 is not scheduled for release yet, and Perl 5 will still be supported
+for quite awhile after its release. Do not wait for Perl 6 to do whatever
+you need to do.
+
+"We're really serious about reinventing everything that needs reinventing."
+--Larry Wall
+
+=head2 How stable is Perl?
+
+Production releases, which incorporate bug fixes and new functionality,
+are widely tested before release. Since the 5.000 release, we have
+averaged only about one production release per year.
+
+Larry and the Perl development team occasionally make changes to the
+internal core of the language, but all possible efforts are made toward
+backward compatibility. While not quite all Perl 4 scripts run flawlessly
+under Perl 5, an update to perl should nearly never invalidate a program
+written for an earlier version of perl (barring accidental bug fixes
+and the rare new keyword).
+
+=head2 Is Perl difficult to learn?
+
+No, Perl is easy to start learning--and easy to keep learning. It looks
+like most programming languages you're likely to have experience
+with, so if you've ever written a C program, an awk script, a shell
+script, or even a BASIC program, you're already partway there.
+
+Most tasks only require a small subset of the Perl language. One of
+the guiding mottos for Perl development is "there's more than one way
+to do it" (TMTOWTDI, sometimes pronounced "tim toady"). Perl's
+learning curve is therefore shallow (easy to learn) and long (there's
+a whole lot you can do if you really want).
+
+Finally, because Perl is frequently (but not always, and certainly not by
+definition) an interpreted language, you can write your programs and test
+them without an intermediate compilation step, allowing you to experiment
+and test/debug quickly and easily. This ease of experimentation flattens
+the learning curve even more.
+
+Things that make Perl easier to learn: Unix experience, almost any kind
+of programming experience, an understanding of regular expressions, and
+the ability to understand other people's code. If there's something you
+need to do, then it's probably already been done, and a working example is
+usually available for free. Don't forget Perl modules, either.
+They're discussed in Part 3 of this FAQ, along with CPAN, which is
+discussed in Part 2.
+
+=head2 How does Perl compare with other languages like Java, Python, REXX, Scheme, or Tcl?
+
+Favorably in some areas, unfavorably in others. Precisely which areas
+are good and bad is often a personal choice, so asking this question
+on Usenet runs a strong risk of starting an unproductive Holy War.
+
+Probably the best thing to do is try to write equivalent code to do a
+set of tasks. These languages have their own newsgroups in which you
+can learn about (but hopefully not argue about) them.
+
+Some comparison documents can be found at http://www.perl.com/doc/FMTEYEWTK/versus/
+if you really can't stop yourself.
+
+=head2 Can I do [task] in Perl?
+
+Perl is flexible and extensible enough for you to use on virtually any
+task, from one-line file-processing tasks to large, elaborate systems.
+For many people, Perl serves as a great replacement for shell scripting.
+For others, it serves as a convenient, high-level replacement for most of
+what they'd program in low-level languages like C or C++. It's ultimately
+up to you (and possibly your management) which tasks you'll use Perl
+for and which you won't.
+
+If you have a library that provides an API, you can make any component
+of it available as just another Perl function or variable using a Perl
+extension written in C or C++ and dynamically linked into your main
+perl interpreter. You can also go the other direction, and write your
+main program in C or C++, and then link in some Perl code on the fly,
+to create a powerful application. See L<perlembed>.
+
+That said, there will always be small, focused, special-purpose
+languages dedicated to a specific problem domain that are simply more
+convenient for certain kinds of problems. Perl tries to be all things
+to all people, but nothing special to anyone. Examples of specialized
+languages that come to mind include prolog and matlab.
+
+=head2 When shouldn't I program in Perl?
+
+When your manager forbids it--but do consider replacing them :-).
+
+Actually, one good reason is when you already have an existing
+application written in another language that's all done (and done
+well), or you have an application language specifically designed for a
+certain task (e.g. prolog, make).
+
+For various reasons, Perl is probably not well-suited for real-time
+embedded systems, low-level operating systems development work like
+device drivers or context-switching code, complex multi-threaded
+shared-memory applications, or extremely large applications. You'll
+notice that perl is not itself written in Perl.
+
+Perl remains fundamentally a dynamically typed language, not
+a statically typed one. You certainly won't be chastised if you don't
+trust nuclear-plant or brain-surgery monitoring code to it. And Larry
+will sleep easier, too--Wall Street programs not withstanding. :-)
+
+=head2 What's the difference between "perl" and "Perl"?
+
+One bit. Oh, you weren't talking ASCII? :-) Larry now uses "Perl" to
+signify the language proper and "perl" the implementation of it, i.e.
+the current interpreter. Hence Tom's quip that "Nothing but perl can
+parse Perl."
+
+Before the first edition of I<Programming perl>, people commonly
+referred to the language as "perl", and its name appeared that way in
+the title because it referred to the interpreter. In the book, Randal
+Schwartz capitalised the language's name to make it stand out better
+when typeset. This convention was adopted by the community, and the
+second edition became I<Programming Perl>, using the capitalized
+version of the name to refer to the language.
+
+You may or may not choose to follow this usage. For example,
+parallelism means "awk and perl" and "Python and Perl" look good, while
+"awk and Perl" and "Python and perl" do not. But never write "PERL",
+because perl is not an acronym, apocryphal folklore and post-facto
+expansions notwithstanding.
+
+=head2 Is it a Perl program or a Perl script?
+
+Larry doesn't really care. He says (half in jest) that "a script is
+what you give the actors. A program is what you give the audience."
+
+Originally, a script was a canned sequence of normally interactive
+commands--that is, a chat script. Something like a UUCP or PPP chat
+script or an expect script fits the bill nicely, as do configuration
+scripts run by a program at its start up, such F<.cshrc> or F<.ircrc>,
+for example. Chat scripts were just drivers for existing programs,
+not stand-alone programs in their own right.
+
+A computer scientist will correctly explain that all programs are
+interpreted and that the only question is at what level. But if you
+ask this question of someone who isn't a computer scientist, they might
+tell you that a I<program> has been compiled to physical machine code
+once and can then be run multiple times, whereas a I<script> must be
+translated by a program each time it's used.
+
+Now that "script" and "scripting" are terms that have been seized by
+unscrupulous or unknowing marketeers for their own nefarious purposes,
+they have begun to take on strange and often pejorative meanings,
+like "non serious" or "not real programming". Consequently, some Perl
+programmers prefer to avoid them altogether.
+
+=head2 What is a JAPH?
+
+(contributed by brian d foy)
+
+JAPH stands for "Just another Perl hacker,", which Randal Schwartz used
+to sign email and usenet messages starting in the late 1980s. He
+previously used the phrase with many subjects ("Just another x hacker,"),
+so to distinguish his JAPH, he started to write them as Perl programs:
+
+ print "Just another Perl hacker,";
+
+Other people picked up on this and started to write clever or obfuscated
+programs to produce the same output, spinning things quickly out of
+control while still providing hours of amusement for their creators and
+readers.
+
+CPAN has several JAPH programs at http://www.cpan.org/misc/japh .
+
+=head2 Where can I get a list of Larry Wall witticisms?
+
+(contributed by brian d foy)
+
+Google "larry wall quotes"! You might even try the "I feel lucky" button.
+:)
+
+Wikiquote has the witticisms from Larry along with their source,
+including his usenet postings and source code comments.
+
+If you want a plain text file, try
+http://www.cpan.org/misc/lwall-quotes.txt.gz .
+
+=head2 How can I convince others to use Perl?
+
+(contributed by brian d foy)
+
+Appeal to their self interest! If Perl is new (and thus scary) to them,
+find something that Perl can do to solve one of their problems. That
+might mean that Perl either saves them something (time, headaches, money)
+or gives them something (flexibility, power, testability).
+
+In general, the benefit of a language is closely related to the skill of
+the people using that language. If you or your team can be more faster,
+better, and stronger through Perl, you'll deliver more value. Remember,
+people often respond better to what they get out of it. If you run
+into resistance, figure out what those people get out of the other
+choice and how Perl might satisfy that requirement.
+
+You don't have to worry about finding or paying for Perl; it's freely
+available and several popular operating systems come with Perl. Community
+support in places such as Perlmonks ( http://www.perlmonks.com )
+and the various Perl mailing lists ( http://lists.perl.org ) means that
+you can usually get quick answers to your problems.
+
+Finally, keep in mind that Perl might not be the right tool for every
+job. You're a much better advocate if your claims are reasonable and
+grounded in reality. Dogmatically advocating anything tends to make
+people discount your message. Be honest about possible disadvantages
+to your choice of Perl since any choice has trade-offs.
+
+You might find these links useful:
+
+=over 4
+
+=item * http://perltraining.com.au/whyperl.html
+
+=item * http://www.perl.org/advocacy/whyperl.html
+
+=back
+
+=head1 AUTHOR AND COPYRIGHT
+
+Copyright (c) 1997-2010 Tom Christiansen, Nathan Torkington, and
+other authors as noted. All rights reserved.
+
+This documentation is free; you can redistribute it and/or modify it
+under the same terms as Perl itself.
+
+Irrespective of its distribution, all code examples here are in the public
+domain. You are permitted and encouraged to use this code and any
+derivatives thereof in your own programs for fun or for profit as you
+see fit. A simple comment in the code giving credit to the FAQ would
+be courteous but is not required.