Technology architecture - Technology
Legacy system
An older system still relied on, often difficult to change or replace
What's it for?
Keeps important older technology running until it can safely be replaced or retired.
For example…
Orders still post into a twenty-year-old stock system that nobody wants to touch before year-end
A twenty-year-old payroll application still performs a critical job but is difficult to integrate and depends on skills that are becoming scarce
Think of it like…
An old but essential boiler — it still heats the house, even if parts are scarce