Perl came out on 18 December 1987, when Larry Wall posted version 1.0 to Usenet. Wall, a Unisys programmer with a background in linguistics, wanted something better than gluing together awk, sed and shell scripts to produce reports. Within ten years it was running much of the early web's dynamic pages, which is why Perl is known as internet duct tape: it was cheap, flexible, a bit messy, and it held almost anything together.
Origins: a report tool that kept growing
Wall originally wanted to call the language "Pearl", but another language named PEARL already existed, so he dropped the "a". The expansion "Practical Extraction and Report Language" was attached afterward, along with Wall's own joke version, "Pathologically Eclectic Rubbish Lister". Both describe the language fairly well.
Early releases moved quickly. Perl 2 (1988) brought a better regular expression engine, Perl 3 (1989) handled binary data, and Perl 4 (1991) was mainly a version number to match the first edition of Programming Perl, the O'Reilly book everyone calls "the Camel book". The big leap was Perl 5 in October 1994: references, modules, packages used as classes, and lexical scoping. Nearly every Perl script in use today targets Perl 5.
Design and key features
Wall approached Perl like a linguist. He accepted that people say the same thing in different ways and built that into the motto TMTOWTDI ("There's More Than One Way To Do It"). The result is expressive and compact, and occasionally unreadable when written in a hurry.
- Regular expressions as part of the syntax, not a library call. Perl's regex dialect became so influential that "Perl-compatible regular expressions" (PCRE) now ship inside PHP, Apache, nginx and countless editors.
- Sigils mark variable types:
$scalar,@array,%hash. - Context sensitivity: an expression can behave differently in scalar or list context.
- Automatic memory management through reference counting, plus built-in hashes long before most scripting languages had them.
- CPAN, the Comprehensive Perl Archive Network, which went online in 1995 and set the model later copied by PyPI, RubyGems and npm.
A short Perl example
This script counts word frequencies from standard input, the kind of job Perl was born for:
#!/usr/bin/perl
use strict;
use warnings;
my %count;
while (my $line = <STDIN>) {
$count{lc $1}++ while $line =~ /(\w+)/g;
}
for my $word (sort { $count{$b} <=> $count{$a} } keys %count) {
printf "%-15s %d\n", $word, $count{$word};
}Why Perl is known as internet duct tape
When the web took off in the mid-1990s, servers spoke to programs through CGI, the Common Gateway Interface. Perl was already installed on most Unix machines, handled text effortlessly and needed no compile step. Lincoln Stein's CGI.pm module made form handling trivial, and mod_perl embedded the interpreter directly in Apache for speed. Guestbooks, hit counters, shopping carts and forums were overwhelmingly Perl. The "duct tape" line is usually credited to Hassan Schroeder, Sun's first webmaster, and it stuck because system administrators used Perl the same way: to join tools that were never designed to talk to each other.
Notable software built with Perl includes Slashdot, Bugzilla, Movable Type, cPanel, Request Tracker, the BioPerl toolkit used in genome research, and large parts of early Amazon, Craigslist and Booking.com.
Versions timeline
| Year | Release | Notable change |
|---|---|---|
| 1987 | Perl 1.0 | First public release |
| 1991 | Perl 4 | Matched the first Camel book |
| 1994 | Perl 5.000 | Modules, references, objects |
| 2000 | Perl 6 announced | Start of a ground-up redesign |
| 2010 | Perl 5.12 | Yearly release schedule established |
| 2019 | Perl 6 renamed Raku | Perl 5 line continues as "Perl" |
The Perl 6 project, announced in 2000, took so long that it drifted into a separate language. Its renaming to Raku in 2019 freed Perl 5 to keep evolving under its own name, with signatures, postfix dereferencing and a newer class feature arriving in recent 5.x releases.
Influence and legacy
Perl's fingerprints are everywhere. Ruby borrowed its regex literals and many built-in variables, PHP began life as a set of Perl scripts, and JavaScript's regular expressions follow Perl's syntax closely. Today Perl is less fashionable, but it still runs build systems, monitoring scripts and legacy web apps, and Debian-based systems ship it as a core dependency. The reasons why Perl is known as internet duct tape still hold: it is everywhere, it is quick to reach for, and it rarely lets you down on messy text.
Frequently asked questions
Who first called Perl the duct tape of the internet?
The phrase is usually credited to Hassan Schroeder, who was Sun Microsystems' first webmaster. It spread quickly in the late 1990s because it matched how administrators actually used Perl. It describes Perl's role as glue between tools rather than any official slogan.
Is Perl still used for web development in 2026?
Yes, though far less than in the CGI era. Frameworks such as Mojolicious, Dancer2 and Catalyst are maintained, and many long-running sites still serve Perl code. Most new Perl work today is in system administration, data munging and maintaining existing applications.
What is the difference between Perl and Raku?
Raku started as Perl 6 but became a separate language with a new grammar engine, gradual typing and a different runtime. Code written for Perl 5 does not run unchanged on Raku. The 2019 rename made it clear that Perl 5 continues as Perl.
