Should you do validation on the server side, or is it ok to just do the validation on the client side?
@TheTXI
I am happy your amazed I just did not want to leave anything out that could potential change someone answer to give me false information.
It seems alot of people touched on what I was going after but the part of the Ajax should have been kept in my question as this was the most important part.
However reading the posts I know see that a bad person could just easily load up firebug and change my button to a submit button and do a post. Or some other way.
Browser/client-side validation is a convenience. You cannot rely on it. You absolutely need to duplicate any client-level validation with server-side validation.