The context is that value would be user input in a form. I'm confused about the is_array portion in the 4th line. The user input shown in the book states would be something like an e-mail, name, or comment. I'm confused as to why is_array would be used. I mean when will user input every be an array? Wouldn't that make the condition always true? Anyways, thanks for the reply, I finally understood that last portion at the bottom, which I thought was assigning $key to the $temp variable defined above.