What is Perl?

Perl is a dynamic programming language, created in 1987 by Larry Wall, a linguist at NASA. It was developed as a scripting language, meant to combine the best features of C, sed, and the Bourne Shell. At the time, it was primarily used for administrative tasks, and it still sees some use in this capacity today. Over time, however, it became apparent that this language was ideal in many ways for server-side scripting for web pages, and so grew in popularity in that field, eventually becoming one of the top server-side languages.

The name Perl was apparently derived from the parable of the pearl in the Gospel of Matthew, which reads: "Again, the kingdom of heaven is like unto a merchant man, seeking goodly pearls; Who, when he had found one pearl of great price, went and sold all that he had, and bought it." Wall wanted a name that evoked positive thoughts, and so chose Pearl as the name for the language, but when he discovered a PEARL language already existed, he shifted the spelling. The unofficial symbol for Perl, the camel, comes from the iconic instructional manual for the language, published by O’Reilly Media, which featured a camel on the cover.

The language itself has seen a number of very distinct versions, with each version further refining the language and making it better suit its core purpose. Larry Wall continues to oversee the development of Perl, and helps guide it to stay in connection with its original values. It is incredibly versatile, very flexible, and can be adapted to almost any situation, and as such is a favorite of many programmers, and is often referred to humorously as the "Swiss Army chainsaw" of programming languages.

The first few years of the life of the language saw a great deal of development, with 1988 seeing version 2.0, and 1989 seeing version 3.0. In 1991 the first book on programming in Perl was released, called by most simply the Camel Book after the logo, and at the same time the working version was labeled 4.0 to denote that as the version the book focused on. Perl 5, which saw a massive overhaul, was released in 1994, and remains the current version, although Perl 6 continues to be built.

Version 5.0 saw a massive overhaul of the language. The interpreter itself was written anew, and became more efficient and streamlined. A number of critical components were added, making the language so favored by web developers today. These included references, objects, and variables, all of which had previously not existed, or existed only in limited form. Version 5 also introduced modules, which allowed Perl to essentially be extended without rewriting the interpreter, which is why the language itself could stay virtually static for so many years after such an intense period of change.

1995 saw another key moment in the language's development, although this time from the larger community, and not from the language development itself. It was in that year that the Comprehensive Perl Archive Network (CPAN) opened its doors, acting as a repository for modules that others had built. This meant that Perl’s extensibility could be accessed by anyone, for free, in an easy-to-use archive. The repository eventually grew to include more than 15,000 modules, and helped make it an easy choice for developers.