What Data::Dumper usually does is dump your data in a nice, legible format. There are actually quite a few uses for the module, but most programmers start using it with something like the following:

#!/usr/bin/perl -w
use strict;
use Data::Dumper;
my $foo   = 'test';
my @array = qw/ this is an array /;
my %hash  = (
    one   => 'une',
    two   => 'deux',
    three => \&some_subroutine,
    four  =>
    {
        uh => 'oh',
        name => [qw/Publius Ovidius Naso/]
    }
);
my $bar;
print Dumper $foo, \@array;
print Dumper \%hash;
print Dumper $bar;

[download]

Thus, you can use Data::Dumper to quickly 'dump' the contents of your variables. Yes, you can print a scalar, but printing out complex data structures (like the hash, above) can be tedious. Data::Dumper frees you from the hard work and makes debugging a breeze. If you do CGI work, try dumping the CGI object sometime. It's most informative :)

Once you get used to using Data::Dumper, reread the documentation. It will be easier to understand.

Cheers,
Ovid

Update: For the record, this is the output of the above code:

$VAR1 = 'test';
$VAR2 = [
          'this',
          'is',
          'an',
          'array'
        ];
$VAR1 = {
          'one' => 'une',
          'three' => sub { "DUMMY" },
          'two' => 'deux',
          'four' => {
                      'uh' => 'oh',
                      'name' => [
                                  'Publius',
                                  'Ovidius',
                                  'Naso'
                                ]
                    }
        };
$VAR1 = undef;

[download]

I don't see how munchie could have gotten the output listed below.

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In reply to (Ovid) Re: Data::Dumper in a nutshell? by Ovid
in thread Data::Dumper in a nutshell? by munchie

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