Textfield must contain


I have an emailform, and I’m curious on how you check that if the email textfield contains “@” and “.” move on…
I have this:

if (email eq "") {
Status = "Please enter valid Email ";

That checks if the email field contains nothing show the text in Status field.
(to be honest, I copied that one, and haven’t really a clue what eq really stands for)

thanks in advance