What are different types of computer systems?

Depends of you are talking about different types of operating systems or what exactly. Different opperating systems would be Windows XP or some other level of windows. Could also be a Mac, Lynix, etc etc. Diffenty systems could also be things like "laptops" vs. PC vs. blackberry or other handhelds. Different systems could be something else as well such as brand names like Dell, Gateway etc.

Gotta narrow down your question a little bit if you can onless this has helped already.

One example of system analysis and design concepts is office automation system (OAS).