No more wading through web browser windows and tabs just to read your email or check your Facebook feed. Prism apps run directly on your desktop and can be accessed just like any other application. On Windows, you can launch applications from the Start menu and then access them in the taskbar. On Mac, you can launch and access applications from the OS X dock.
Tray icon and dock menus
When you do something often enough, even a single extra step can be a major hassle. With Prism, the most common features for an application can be added to a tray icon or dock menu. These features can then be accessed in one step, providing significant time savings.
Associate applications with browser links
Some browser links cause an application to run rather than opening in the browser. A popular example are mailto: links that open your mail client and fill out the recipient (and optionally the subject line) for you. Until now, you were out of luck if you use a web mail client, but now Prism lets web apps handle these links just like traditional desktop apps.
Rock solid web app stability
Modern web browsers are pretty stable, but then can still crash due to a rogue application or elusive bug. Prism apps run separately from the browser, so they stay up even if your browser doesn't. Separating apps also reduces browser load, improving performance and stability.
Run applications automatically when your computer starts
Some web apps are so important that we want them running all the time. For some users this might mean Gmail, Facebook or Flickr. With Prism you can set an app to run automatically whenever your start your computer.
System tray icon and dock badges
On Windows, the system tray icon can be changed to give information about application status (e.g. adding a star to show that your web mail has new messages). On Mac, a badge can be added to the dock icon for the same purpose.
from :http://prism.mozillalabs.com
