The difference is that a local replaces a global in the current block and in any subroutines that are called from the current block. my is only in effect for the enclosing block (or package thanks revdiablo or file). 
use strict;
use warnings;

our ($x, $y) = ('global X', 'global Y');
example();

sub example {
  local $x;
  my $y;
  $x = 'changed local';
  $y = 'changed my';
  example2();
}

sub example2 {
  print "X: $x, Y: $y\n";
}

[download]
example2 will print the $x that is local to example, but the global $y.
Caution: Contents may have been coded under pressure.

In reply to Re: Difference my and local by Roy Johnson
in thread Difference my and local by Anonymous Monk

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