This widget sticks the header - and its contents - to the top of the browser so that they always remain in view.
This has the advantage of always having the the navigation menu on hand without the visitor needing to scroll to get to it.
Another good thing about this is that the website name and logo can be seen at all times and the visitor is less likely to forget it!
Since the header, the <h1> HTML Heading and navigation should be the same for every page of the site, they can be set up on a master or a template page.
The header should be installed first - before any other content such as website name, logo etc.