use warnings;
use strict;

my %passwords = ( Matt => "s1k1d52",
                  scuzzy => "2ab928",
                  Marky => "s8291s",
                  Jeb => "jeb23" );

delete $passwords{jeb}; # <-- Update, MidLifeXis notes the casing in "jeb" is wrong.

if( exists $passwords{Matt} )
{
    print "$passwords{Matt} is my password.\n";
}

if( defined $passwords{scuzzy} )
{
    print $passwords{scuzzy} . " IS defined!\n";
}

print join(", ", values %passwords), " are everyone's passwords!\n";