The word lock came from Anglo-Saxon loca = "a secure enclosure". Currently lock has several meanings: A lock (device) is a mechanical fastening device which may be used on a door, vehicle, safe, or other container. Commonly, it can be released by using a key or combination. See locksmithing. A canal lock is an enclosure in a canal or river used to raise or lower the water level for ships and boats passing through. A lock (computer science) is a bookkeeping object

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