help in understanding a regex

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

 

#!/usr/local/bin/perl -w
$string = "/dir1/dir8/dir2";
$string =~ m|([^/]+)$|;
print $1;
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if i change the line of code as $string =~ m/([^/]+)$/ it doesent work.