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An Introduction to the Perl Programming Language

If you already are experienced in programming C, C++, or Java, Perl should be very easy to learn. It is a langauge that may make your days programming C or C++ very short-lived... Perl is an easy langauge that is both powerful and portable.
Pratical Extraction and Report Language or Perl for short, was created by Larry Wall. Perl is an interpreted language, thus is penalized for speed (as is Java), but it isn't noticeable in relatively manageable programs because the Perl interpreter is written in very fast C.

Perl Introduction :: Hello, World!

Let's begin our journey into Perl with a simple Perl program that prints out Hello, World! (let's call our file hello.pl):
```
  #!/usr/bin/perl

  print "Hello, World!\n";
```
Amazed? Don't be. Perl is supposed to be this simple, a stark contrast to other languages. The first line signifies where the perl interpreter resides on the host system. This is usually /usr/bin/perl on Linux systems and /bin/perl under *NIX systems. The next statment is a simple print statement. That's it.
The perl interpreter has useful switches. The -c switch lets perl check for syntax only, without running the actual program. The -w turns on all useful warnings. You should ALWAYS develop your programs under -w.
So how would you actually run this program? You could run it as:
```
  perl -w hello.pl
```
or we could make the perl file executable, by using the chmod command:
```
  chmod 700 hello.pl
  ./hello.pl
```
But then you ask, how do I issue the -w flag? Simple, put it in the perl line at line 1. #!/usr/bin/perl -w.
A comment in Perl begins with #.

Perl Introduction :: The Journey Ahead

As you can see, Perl isn't meant to be confusing or difficult. It is rather easy to learn and isn't that difficult to implement if once you learn the basics.
You may be shocked that we are already heading into Data Structures in the next section, but these fundamental data types are necessary for you to do anything useful in Perl.
One of the strengths of Perl is it's regular expression and string manipulation capability... We'll get to that in the Beyond Perl Section later.
On the surface Perl looks like a straight up functional programming language, but Perl can actually be Object-Oriented. Should you always use OO programming in Perl? Probably not for all tasks, but it could prove to be useful later.

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