The split is done in scalar context ($_ is scalar and sets the context) so the assignment is counting the number of pieces you get, one more than the number of &'s. The following line executes blah.pl using backticks to collect the text output of the script and print it after a paragraph tag.

You should toss this and start over. You are handrolling a cgi query parser when you should use CGI;. It will do a much better job.

After Compline,
Zaxo