man > perlfaq1(1)

PERLFAQ1(1)                       Perl Programmers Reference Guide                       PERLFAQ1(1)

NAME
       perlfaq1 - General Questions About Perl

VERSION
       version 5.20210520

DESCRIPTION
       This section of the FAQ answers very general, high-level questions about Perl.

   What is Perl?
       Perl is a high-level programming language with an eclectic heritage written by Larry Wall and
       a cast of thousands.

       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 web programming.

       Perl derives from the ubiquitous C programming language and to a lesser extent from sed, awk,
       the Unix shell, and many other tools and languages.

       These strengths make it especially popular with web developers and system administrators.
       Mathematicians, geneticists, journalists, managers and many other people also use Perl.

   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.

       The core development team (known as the Perl Porters) are a group 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
       <http://www.nntp.perl.org/group/perl.perl5.porters/> or you can subscribe to the mailing list
       by sending perl5-porters-subscribe AT 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.

   Which version of Perl should I use?
       (contributed by brian d foy with updates from others)

       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.

       Beyond that, you have to consider several things and decide which is best for you.

       •   If things aren't broken, upgrading perl may break them (or at least issue new warnings).

       •   The latest versions of perl have more bug fixes.

       •   The latest versions of perl may contain performance improvements and features not present
           in  older  versions.   There  have  been  many  changes  in  perl  since  perl5 was first
           introduced.

       •   The Perl community is geared toward supporting the most recent releases, so  you'll  have
           an easier time finding help for those.

       •   Older  versions of perl may have security vulnerabilities, some of which are serious (see
           perlsec and search CVEs <https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=Perl> for  more
           information).

       •   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.

       •   The immediate, in addition to the current stable release, the previous stable release  is
           maintained.  See "MAINTENANCE AND SUPPORT" in perlpolicy for more information.

       •   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. perl5.24.x, where 24 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. perl5.25.x, where 25 is the minor release).

       •   You  can  consult  releases  <http://dev.perl.org/perl5>  to determine the current stable
           release of Perl.

   What are Perl 4, Perl 5, or Raku (Perl 6)?
       In short, Perl 4 is the parent to both Perl 5 and Raku (formerly known as Perl 6). Perl 5  is
       the  older  sibling, and though they are different languages, someone who knows one will spot
       many similarities in the other.

       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, first released in 1994. It can run scripts  from
       the previous major release, Perl 4 (March 1991), but has significant differences.

       Raku is a reinvention of Perl, a language in the same lineage but not compatible. The two are
       complementary, not mutually exclusive. Raku is not meant to replace Perl, and vice versa. See
       "What is Raku (Perl 6)?"  below to find out more.

       See perlhist for a history of Perl revisions.

   What is Raku (Perl 6)?
       Raku  (formerly known as Perl 6) was originally described as the community's rewrite of Perl,
       however as the language evolved, it became clear that it is a separate language, but  in  the
       same language family as Perl.

       Raku  is  not  intended  primarily  as  a  replacement  for  Perl, but as its own thing - and
       libraries exist to allow you to call Perl code from Raku programs and vice versa.

       Contrary to popular belief, Raku and Perl peacefully  coexist  with  one  another.  Raku  has
       proven to be a fascinating source of ideas for those using Perl (the Moose object system is a
       well-known  example).  There  is  overlap  in  the  communities, and this overlap fosters the
       tradition of sharing and borrowing that have been instrumental to Perl's success.

       For more about Raku see <https://www.raku.org/>.

       "We're really serious about reinventing everything that needs reinventing."  --Larry Wall

   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 about one production release per
       year.

       The Perl development team occasionally make changes to the internal core of the language, but
       all possible efforts are made toward backward compatibility.

   How often are new versions of Perl released?
       Recently, the plan has been to release a new version of Perl roughly every April, but getting
       the release right is more important than sticking rigidly to a calendar date, so the  release
       date   is   somewhat   flexible.    The   historical   release   dates   can   be  viewed  at
       <http://www.cpan.org/src/README.html>.

       Even numbered minor versions (5.14, 5.16, 5.18) are production  versions,  and  odd  numbered
       minor  versions  (5.15,  5.17,  5.19) are development versions. Unless you want to try out an
       experimental feature, you probably never want to install a development version of Perl.

       The Perl development team are called Perl 5 Porters, and their organization is  described  at
       <http://perldoc.perl.org/perlpolicy.html>.  The organizational rules really just boil down to
       one: Larry is always right, even when he was wrong.

   Is Perl difficult to learn?
       No,  Perl  is easy to start learning <http://learn.perl.org/> --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 <http://www.cpan.org/>, which is discussed
       in Part 2.

   How does Perl compare with other languages like Java, Python, REXX, Scheme, or Tcl?
       Perl can be used  for  almost  any  coding  problem,  even  ones  which  require  integrating
       specialist  C  code  for extra speed. As with any tool it can be used well or badly. Perl has
       many strengths, and a few weaknesses, precisely which areas are  good  and  bad  is  often  a
       personal choice.

       When   choosing   a   language   you   should   also   be   influenced   by   the   resources
       <http://www.cpan.org/>,   testing   culture   <http://www.cpantesters.org/>   and   community
       <http://www.perl.org/community.html> which surrounds it.

       For  comparisons  to  a  specific language it is often best to create a small project in both
       languages and compare the results, make sure to use all the resources  <http://www.cpan.org/>
       of each language, as a language is far more than just it's syntax.

   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 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.

   When shouldn't I program in Perl?
       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).

       If  you  find  that you need to speed up a specific part of a Perl application (not something
       you often need) you may want to use C, but you can access  this  from  your  Perl  code  with
       perlxs.

   What's the difference between "perl" and "Perl"?
       "Perl" is the name of the language. Only the "P" is capitalized.  The name of the interpreter
       (the program which runs the Perl script) is "perl" with a lowercase "p".

       You  may  or may not choose to follow this usage. But never write "PERL", because perl is not
       an acronym.

   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>.

   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 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:

       •   <http://www.perl.org/about.html>

       •   <http://perltraining.com.au/whyperl.html>

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.

perl v5.38.2                                 2026-06-12                                  PERLFAQ1(1)