I'm having problems installing PHP with Apache on RedHat 7

Hi all. I'm using ReHat 7 with the latest versions of Apache and php (4). I've done all the steps to install php with apache but when I create code in php the webserver doesn't recognize the code, I only can code in HTML! Something is missig, can you tell me what? Thanks, regards, Hugo Sousa - A Newbie in PHP world! :) **** This message is from Arthur D. Little, Inc., and/or one of Arthur D. Little's subsidiaries or affiliates and may contain confidential business information. It is intended for the addressee only and may not be copied without our permission. If you are not the intended recipient please contact the sender as soon as possible.****