A legacy system is software, programming language, application programs or other technology that is, simply put, outdated—though sometimes the term can refer to technology that is still up-to-date, but no longer receiving vendor support, for whatever reason.
Legacy systems are looked on as a detriment to an organization when circumstances like cost or compatibility require continued usage of such systems. Even if an organization has moved on to more advanced technology, the effect of legacy systems can linger when old data remains in legacy format. To help solve this particular problem, schema crosswalk can be customized to help translate data into a new system.
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