It is Safari. Like Safari on the iPhone, you can have multiple pages open at once. On the iPhone, Safari displays pages like Cover Flow, allowing you to swipe through a list. On the iPad, Safari presents them in a grid a little like the Top Sites feature of the desktop Safari. Type iPad Safari in Youtube and you will see plenty of videos showing you how it works. He doesn't have many videos on the iPad and doesn't cover all the apps, but Zollotech on Youtube has a decent Safari demo.