Applications act as a front end interface for a user, while the database is where the data is actually stored.

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Unlike OnLive, Playcast can tailor its front-end interface with specific branding according to its customers' desires, and it works on your TV without the need for special hardware.

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Facebook is just the front end -- the consumer interface -- of a big data engine.

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However you feel about the new interface, that transition is at last complete: Outlook.com is now the sole front end for the over 400 million people who use Microsoft's free email services.

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