People generally predeclare with my to assist with error-checking. If you add the pragma use strict; to the top of your program, all variables have to be declared with my or our before they're used. This helps eliminate errors due to variable name typos.

For example: 

use strict;
my $typo;
$tuypo = "Here's some data: $data";
print $typo;

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will produce an error.

In reply to Re: Predeclaration by Anonymous Monk
in thread Predeclaration by hakkr

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