MUMPS (Massachusetts General Hospital Utility Multi-Programming System), or alternatively M, is a programming language created in the late 1960s, originally for use in the healthcare industry. It was designed for the production of multi-user database-driven applications. It predates C and most other popular languages in current usage, and has very different syntax and terminology. Its most unique and differentiating feature is the "built-in" database, enabling high-level access to disk storage using simple symbolic program variables, similar to the variables used by most languages to access main memory.
It was largely adopted during the 1970s and early 1980s in healthcare and financial information systems/databases, and continues to be used by many of the same clients today. It is currently used in electronic health record systems as well as by multiple banking networks and online trading/investment services.
Read more about MUMPS: History, Current Users of MUMPS Applications, Overview, "Hello, World!" Example, Summary of Key Language Features, "MUMPS" Vs. "M" Naming Debate, Epoch Choice, Sample Programs