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* Errors: Errors are easily recovered from. There won't be any mode errors since there aren't different modes of operation. If the user clicks the wrong stream, all he has to do is go back on his browser. Similarly, other operations like searching and selecting a category are reversible by simply choosing the right thing after an error.
Design 3
Storyboard
This is the view that the user would see when they first get to the page. There is a title bar at the top showing SB representing StreamBrowser and a search box to the left. At the bottom of the page would be a playlist of previously viewed streams or any that are queued up. This is hidden while the playlist is empty. In the middle section , to the left would be the categories listing, and is the categories listing.
Once the user has selected a category, to the right, the recommended streams within the selected category will appear. When the user clicks a new category, the list to the right updates to show streams in that category. If . When the user hovers over the title of a stream, it will show a popup with a short description and actions the user can perform.
If the user is to type any queries in the search box at the top, it would update the list just as it did while selecting new categories. 
This is the small stream viewer. The main list view turns into a viewer for the stream and begins playing the stream.
This is the expanded view for the viewer. The titlebar and category sections go away, leaving the video and playlist. This playlist does go away after a short delay, providing the video the full screen to display the stream.
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