To build on Ultra's reply, it may be a directive for a text editor. For example my editor, JED, opens in perl mode based on extension (.pl) and/or shebang line. But for my modules I did not set up an association. I always put a 
# -*- Perl -*-

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comment at the top of them instead.

In reply to Re: Perl interpretation of weird #! line by blazar
in thread Perl interpretation of weird #! line by jesuashok

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