According to Google, there are currently more than 500 million objects about which they can display information from a database of 3.5 billion facts.

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Front-end applications access the database to display data online.

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Issued today, the USPTO's database details a messaging system where users can follow each other and display messages without a unique recipient.

ENGADGET

As good as these systems are, they do have one shortcoming: Their ability to display obstacles like bridges, towers, cranes and the like is solely based on a pre-loaded database.

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