Technology Fundamentals
Legacy System
Definition
A legacy system refers to an outdated computing software and/or hardware that is still in use. The system still meets the needs it was originally designed for, but may be unstable, difficult to maintain, and incompatible with modern equivalents.
Why It Matters
Many large organizations (like banks, governments, and airlines) still rely on legacy systems to run their core operations. Maintaining, updating, or replacing these systems is a massive and expensive challenge.
Contextual Example
A bank's core transaction processing system might still be running on a mainframe computer with code written in COBOL 40 years ago. It works, but finding programmers who know COBOL is difficult and integrating it with modern web services is complex.
Common Misunderstandings
- "Legacy" is not just about age; it's about being based on obsolete technology.
- The decision to replace a legacy system is a difficult business decision, weighing the risks and costs of the old system against the risks and costs of a migration project.