Answer 1

I will assume you created a form in a PHP script and tried doing the validation on the same page, well this is what happened your script runs and comes across a variable that has no value (because you have not submitted a form data ) hence because it doesn't know whether the variable is a number string or object it tells you it is undefined. when you submit the form the error should go out but if it doesn't check that the variable you are trying to use is what you defined it to be. hope this helps next time give a clear explanation of what you did