Displaying Form Errors

Hello all, I am building a web page and I don't know how to display the errors that the user may enter. OK this is how I have my web page setup: I first do a isset check on $submit. And I am not sure about this. I believe that this variable is set when i click on the submit button. I don't have a $submit variable assigned to anything in my web page. What I would like is to have $submit assigned to the submit button. How do I do that? In the if block I do my validation of the web form. In the else block I have the contents of the page. I have posted this question before and I got some good pointers on how I should go about doing my validation but I have not yet figured out how to display the errors on the page. Could someone help me with that. I am doing the validation on the same page as the web page. I don't forward to a new page to do the validation. Thanks Paul