Computer security: The sounds of individual keystrokes can be distinguished, making it possible to eavesdrop on computer users

CLATTERING keyboards may seem the white noise of the modern age, but they betray more information than unwary typists realise. Simply by analysing audio recordings of keyboard clatter, computer scientists can now reconstruct an accurate transcript of what was typed—including passwords. And in contrast with many types of computer espionage, the process is simple, requiring only a cheap microphone and a desktop computer.
 

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