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<h1><a>perlfaq1 - General Questions About Perl</a></h1>
<p><a name="__index__"></a></p>
<!-- INDEX BEGIN -->
<ul>
<li><a href="#name">NAME</a></li>
<li><a href="#description">DESCRIPTION</a></li>
<ul>
<li><a href="#what_is_perl">What is Perl?</a></li>
<li><a href="#who_supports_perl_who_develops_it_why_is_it_free">Who supports Perl? Who develops it? Why is it free?</a></li>
<li><a href="#which_version_of_perl_should_i_use">Which version of Perl should I use?</a></li>
<li><a href="#what_are_perl4__perl5__or_perl6">What are perl4, perl5, or perl6?</a></li>
<li><a href="#what_is_ponie">What is Ponie?</a></li>
<li><a href="#what_is_perl6">What is perl6?</a></li>
<li><a href="#how_stable_is_perl">How stable is Perl?</a></li>
<li><a href="#is_perl_difficult_to_learn">Is Perl difficult to learn?</a></li>
<li><a href="#how_does_perl_compare_with_other_languages_like_java__python__rexx__scheme__or_tcl">How does Perl compare with other languages like Java, Python, REXX, Scheme, or Tcl?</a></li>
<li><a href="#can_i_do__task__in_perl">Can I do [task] in Perl?</a></li>
<li><a href="#when_shouldn_t_i_program_in_perl">When shouldn't I program in Perl?</a></li>
<li><a href="#what_s_the_difference_between_perl_and_perl">What's the difference between "perl" and "Perl"?</a></li>
<li><a href="#is_it_a_perl_program_or_a_perl_script">Is it a Perl program or a Perl script?</a></li>
<li><a href="#what_is_a_japh">What is a JAPH?</a></li>
<li><a href="#where_can_i_get_a_list_of_larry_wall_witticisms">Where can I get a list of Larry Wall witticisms?</a></li>
<li><a href="#how_can_i_convince_my_sysadmin_supervisor_employees_to_use_version_5_5_6_1_perl_instead_of_some_other_language">How can I convince my sysadmin/supervisor/employees to use version 5/5.6.1/Perl instead of some other language?</a></li>
</ul>
<li><a href="#author_and_copyright">AUTHOR AND COPYRIGHT</a></li>
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<h1><a name="name">NAME</a></h1>
<p>perlfaq1 - General Questions About Perl ($Revision: 1.19 $, $Date: 2005/12/31 00:54:37 $)</p>
<p>
</p>
<hr />
<h1><a name="description">DESCRIPTION</a></h1>
<p>This section of the FAQ answers very general, high-level questions
about Perl.</p>
<p>
</p>
<h2><a name="what_is_perl">What is Perl?</a></h2>
<p>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.</p>
<p>
</p>
<h2><a name="who_supports_perl_who_develops_it_why_is_it_free">Who supports Perl? Who develops it? Why is it free?</a></h2>
<p>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 <a href="../../lib/Pod/perlhist.html">the perlhist manpage</a> (new as of 5.005)
for Perl's milestone releases.</p>
<p>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
<a href="http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/">http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/</a>
and <a href="http://archive.develooper.com/perl5-porters@perl.org/">http://archive.develooper.com/perl5-porters@perl.org/</a>
or the news gateway <a href="nntp://nntp.perl.org/perl.perl5.porters">nntp://nntp.perl.org/perl.perl5.porters</a> or
its web interface at <a href="http://nntp.perl.org/group/perl.perl5.porters">http://nntp.perl.org/group/perl.perl5.porters</a> ,
or read the faq at <a href="http://simon-cozens.org/writings/p5p-faq">http://simon-cozens.org/writings/p5p-faq</a> ,
or you can subscribe to the mailing list by sending
<a href="mailto:perl5-porters-request@perl.org">perl5-porters-request@perl.org</a> a subscription request
(an empty message with no subject is fine).</p>
<p>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.</p>
<p>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.</p>
<p>
</p>
<h2><a name="which_version_of_perl_should_i_use">Which version of Perl should I use?</a></h2>
<p>(contributed by brian d foy)</p>
<p>There is often a matter of opinion and taste, and there isn't any
one answer that fits anyone. In general, you want to use either
the current stable release, or the stable release immediately prior
to that one. Currently, those are perl5.8.x and perl5.6.x, respectively.</p>
<p>Beyond that, you have to consider several things and decide which
is best for you.</p>
<ul>
<li>
<p>If things aren't broken, upgrading perl may break
them (or at least issue new warnings).</p>
</li>
<li>
<p>The latest versions of perl have more bug fixes.</p>
</li>
<li>
<p>The Perl community is geared toward supporting the most
recent releases, so you'll have an easier time finding help for
those.</p>
</li>
<li>
<p>Versions prior to perl5.004 had serious security problems with
buffer overflows, and in some cases have CERT advisories (for
instance, <a href="http://www.cert.org/advisories/CA-1997-17.html">http://www.cert.org/advisories/CA-1997-17.html</a> ).</p>
</li>
<li>
<p>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.</p>
</li>
<li>
<p>The immediate, previous releases (i.e. perl5.6.x ) are usually
maintained for a while, although not at the same level as the
current releases.</p>
</li>
<li>
<p>No one is actively supporting perl4.x. 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.</p>
</li>
<li>
<p>There is no perl6.x for the next couple of years. Stay tuned,
but don't worry that you'll have to change major versions of Perl
soon (i.e. before 2006).</p>
</li>
<li>
<p>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. perl5.8.x, where 8 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).</p>
</li>
</ul>
<p>
</p>
<h2><a name="what_are_perl4__perl5__or_perl6">What are perl4, perl5, or perl6?</a></h2>
<p>(contributed by brian d foy)</p>
<p>In short, perl4 is the past, perl5 is the present, and perl6 is the
future.</p>
<p>The number after perl (i.e. the 5 after perl5) 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.</p>
<p>The current major release of Perl is perl5, and was released in 1994.
It can run scripts from the previous major release, perl4 (March 1991),
but has significant differences. It introduced the concept of references,
complex data structures, and modules. The perl5 interpreter was a
complete re-write of the previous perl sources.</p>
<p>Perl6 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 perl5, and some perl5 modules allow you to use some
perl6 syntax in your programs. You can learn more about perl6 at
<a href="http://dev.perl.org/perl6/">http://dev.perl.org/perl6/</a> .</p>
<p>See <a href="../../lib/Pod/perlhist.html">the perlhist manpage</a> for a history of Perl revisions.</p>
<p>
</p>
<h2><a name="what_is_ponie">What is Ponie?</a></h2>
<p>At The O'Reilly Open Source Software Convention in 2003, Artur
Bergman, Fotango, and The Perl Foundation announced a project to
run perl5 on the Parrot virtual machine named Ponie. Ponie stands for
Perl On New Internal Engine. The Perl 5.10 language implementation
will be used for Ponie, and there will be no language level
differences between perl5 and ponie. Ponie is not a complete rewrite
of perl5.</p>
<p>For more details, see <a href="http://www.poniecode.org/">http://www.poniecode.org/</a></p>
<p>
</p>
<h2><a name="what_is_perl6">What is perl6?</a></h2>
<p>At The Second O'Reilly Open Source Software Convention, Larry Wall
announced Perl6 development would begin in earnest. Perl6 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.</p>
<p>If you want to learn more about Perl6, or have a desire to help in
the crusade to make Perl a better place then peruse the Perl6 developers
page at <a href="http://dev.perl.org/perl6/">http://dev.perl.org/perl6/</a> and get involved.</p>
<p>Perl6 is not scheduled for release yet, and Perl5 will still be supported
for quite awhile after its release. Do not wait for Perl6 to do whatever
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