How do you do this:

I want a form where people add their name and email address with a submit button.

But I don't want them to be able to continue until a valid email is submitted.

Is this possible?

Thanks

For starters, if you are willing to learn a little bit, check out regular expressions. They are a bit confusing to start, but they are very very useful.

Edit:
Forgot the link :D
http://www.javascriptkit.com/javatutors/re.shtml