What is CICS?

When you think of Big Business, you think of Fortune 500 companies. When you think of Big Business software, you think of companies like IBM and Oracle. It's IBM in this case that is the author of CICS, Customer Information Control System, which is also used by a wide variety of financial institutions, colleges and universities, airline reservation systems, insurance companies, ATM systems, and state and national governments.

CICS is a transaction processing system that can handle both small and large numbers of transactions, although it is designed mainly for huge numbers. The top transaction number so far recorded is in the several thousands per second. The functionality extends from traditional mainframes to online batch activity as well.

Not one to be left behind, IBM has versions of CICS that are Web-based and incorporate Enterprise Java Beans. Far from being just a transaction handler, CICS performs all manner of other important system functions as well, including batch job submissions, catalog updating, domain management, and application bridging. This is one powerful system.

CICS was developed in and runs primarily on IBM's 64-bit z/OS, although it can run on other operating systems, including z/VSE, i5, and OS/2. Related systems can also operate on third-party OS systems, including AIX, Linux, Mac OS, and Windows. The vast majority of CICS systems, however, are powered by Big Blue. Originally developed in the U.S. in 1969 for small and medium mainframe systems, CICS now owes its updates for enterprise and other massive-system protocols to programmers working in the United Kingdom. The latest release is CICS Transaction Server Version 3.1 for Z/OS, which launched in 2005.

The pronunciation of the acronym is inconsistent across the world. In English-speaking countries, it is pronounced by saying each letter or by making the initial C hard, to sound like "kicks." Germans say "zicks," and Italians say "chicks." In Spain, it is "thicks," and in Brazil and Mexico it is "sicks."