gmail filter to read only unread messages

One of the nice features of GMail is the advanced search. These are basically a set of commands or operators that perform special actions. The problem is I tend to forget about them so this post is more for my purpose than anyone else's. So after going through the docs I got this to find all my unread messages in my inbox via the following in the search box Find all of them at http://mail.google.com/support/bin/answer.py?hl=en&answer=7190