Users can practice this with, for instance, leaving the house without checking the door lock multiple times, over a given time period.

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Without Vonn, who was a virtual lock for multiple medals, it's a taller task.

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The company received a patent in 1865 and created one of the most important lock inventions, the Yale cylinder lock, a lock mechanism that uses pins of multiple lengths to prevent the lock from opening without the correct key.

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Now, Qualcomm is a promising telecom company with a lock on a technology (called code division multiple access) that is becoming the standard for digital cell phones.

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When you solve multiple custom problems with the same platform, the lock-in is stronger still.

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