In spite of these inherent limitations, many large organizations still use flat files for their general ledger and other financial systems. Most members of the data processing community assumed that the end of the century would see the end of legacy systems. Instead, corporate America invested billions of dollars making these systems year-2000 (Y2K) compliant. Legacy systems continue to exist because they add value for their users, and they will not be replaced until they cease to add value. Students who may have to work with these systems in practice should be aware of their key features.