Replication is the act of creating (normally automatically) a duplicate copy of a database or file system on a different computer. The term usually implies the intelligent copying of parts of the source database which have changed since the last replication with the destination.
Replication may be one-way or two-way. Two-way replication is much more complicated because of the possibility that a replicated object may have been updated differently in the two locations in which case some method is needed to reconcile the different versions.
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