PAR

PAR is for Perl as JAR is for JAVA.

Its used to bundled your perl scripts/modules together for easy deployment at client-side. Its easy to maintain, update and since its zipped, easy to download. The resulting PAR file contains all the dependent modules and needs only core Perl at the client machine. pp - eliminates the need to have core Perl at client machine.

A nice tutorial at http://www.autrijus.org/par-intro/TABLE_OF_CONTENTS.html

User defined constants

You can make your own constants in Perl. (something like #define PI or const
inst PI)

use constant {PI=>3.14, PI2=>3.1416};
print PI ."\n". PI2;

Perl Resources

I think that 'Learning Perl' by Randal L. Schwartz, Tom Phoenix is a book to start with. It enough to get you started with Perl. One thing to remember is that in Perl "there is more than one way to do it" (TIMTOWTDI). So you don't need to know everything there is in Perl before you make your first program in Perl (and I am talking about more than just a print 'Hello World' program).

The next book to go for is the Bible - 'Programming in Perl' by Larry Wall, Tom Christiansen and Randal Schwartz.

If you are looking for some online resource, learn.perl.org is a good place.

In case you have a Perl doubt then you can always turn to comp.lang.perl.misc newsgroup. This is a very active newsgroup but be sure to read the posting guidelines first.

Fundamentals of Software Development

Before we actually discuss some tit-bits of Perl, let us get our fundamentals of software development right.

Please read this article by Barry.