In general, hash changes are created whenever a link is clicked in jQuery mobile. When a link is clicked, jQuery mobile will make sure that the link is referencing a local URL, and if so, it'll prevent the link's default click behavior from occurring and request the referenced url via Ajax instead. When the page returns successfully, it will set the location.hash  to the new page's relative url.

Hash changes that occur independently of a click, such as when a user clicks the back button, are handled through thehashchange event, which is bound to the window object using Ben Alman's hashchange special event plugin (included in jQuery Mobile). When a hash change occurs (and also when the first page loads), the hashchange event handler will send the location.hash to the $.mobile.changePage() function, which in turn either loads or reveals the referenced page.

1. link click -> ajax request(successful) -> update location.hash
   (from the first paragraph)
   
   
   
   
2. link click -> update location.hash -> hashchange event(trigger) -> changePage(called by hashchange event handler)
   (from the second paragraph)