The jQuery Mobile “page” structure is optimized to support either single pages, or local internal linked “pages” within a page.
The goal of this model is to allow developers to create websites using best practices — where ordinary links will “just work” without any special configuration — while creating a rich, native-like experience that can’t be achieved with standard HTTP requests.

http://jquerymobile.com/demos/1.0a4.1/#docs/pages/docs-pages.html