What is the purpose of the locks

Locks are used to make a river more easily navigable, or to allow a canal to cross land that is not level. Later canals used more and larger locks to allow a more direct route to be taken.

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Door locks are used externally to limit entrance into private home and public buildings. The type of locks been used externally includes: Mortise Lock: this is a complete set of locks encased in a square or rectangular shaped metal box to provide the lock with the needed security!!