A
legacy system is an older
computer system that has become too important to replace with newer
technology. Old systems typically become legacy systems after excessive in-house
customization has made the
software incapable of being replaced or even
upgraded. Legacy systems which are seriously
obsolete often require the upkeep of aging
mainframe hardware, which can be expensive to maintain.
I.T. vendors and
consultants can smell the
desperation of a customer with a legacy system, which is yet another reason why it costs so much extra to maintain older hardware and software.
Legacy systems also imply that migrating to newer software would be a long and painful process, so many shops opt instead to place
intermediary systems between the legacy system and their customers and staff. These intermediary systems can minimize the hassles imposed by the legacy system in a number of ways, including a
telephony or
web-based interface, and new software which automates otherwise
tedious tasks on the legacy system. However, if the cost of keeping the legacy system alive becomes too high, most organizations will ultimately
pull the plug and
install something new.