One nice way to learn about hashes, arrays, scalars and references, is
to learn the perl debugger and just experiment.
There is a perl debugger tutorial in the perl documentation.
You can print out the arrays and hashes w/o putting print statements
into your code, and that makes the
Undefined subroutine main::param called at simpleform.cgi line 6.
Is the error I get for your script when I execute it from
http://www.mikyo.com/cgi-bin/simpleform.cgi
If you want to try what I did, do the following:
1. type in http://www.mikyo.com/cgi-bin/simpleform.cgi to your web
browser