In any organization there are many different computer systems. These systems are comprised of computers, software, and networks. They come from different vendors - but they all need to work together to meet the needs of the business - and thus Systems Integration is born. These systems may have been purchased over the course of many years and run on totally different technologies - but at some point they are probably going to be required to work together.
We are specifically going to discuss IT systems integration in this class, but you should recognize that this can be a much larger topic that covers even mechanical systems.
You should read the article links below - these would provide the answers to many of the questions you will be asked to understand the basic idea of systems integration.
Wikipedia on Systems Integration - https://en.wikipedia.org/wiki/System_integration
Software Engineering Institute - http://www.sei.cmu.edu/productlines/frame_report/softwareSI.htm
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