Microsoft has been granted the Page Up Page Down patent. US Patent 7,415,666 goes under the snappy title of: “Method and system for navigating paginated content in page-based increments” and is the latest to be granted to that serial patent application junkie better known as Microsoft.
So what could a method of navigating paginated content, or stuff on the page, using page-based increments possibly refer to? Ding! Of course, the PgUp and PgDn keys.
Look at the abstract description on that patent and you will see that what Microsoft has cleverly managed to grab ownership of is:
“A method and system in a document viewer for scrolling a substantially exact increment in a document, such as one page, regardless of whether the zoom is such that some, all or one page is currently being viewed.”