Extract string after removing the substring

viktor has asked for the wisdom of the Perl Monks concerning the following question:

Hi All,

I am new perl programmer may be its easy but I would like to know how I can extract the string after removing the substring e.g

$string="ATATTTATATTAT";
$removed=substr($string,0,3)
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Now the $removed contains ATA but I want to extract the rest so that now my $string should contain TTTATATTAT.