Page return alternative techniques

I want to do the usual password - username test and send a "success" or a
"fail" page back to the browser.

I started using lines of "print" statements when I did this ages ago, but
quickly moved to using here statements imbedded in the script.

I am looking for other alternatives - alternatives that may enable changes
to the content of the fail and success pages without having to edit the
actual perl script.

Any suggestions?

John