What does an Information System mean to you?
An Information System, to me at least, is a system for collecting and distributing information. These systems usually use some form of computing and there is normally some “doing” going on in there too, such as calculating with numbers or producing documentation.
These ISs normally have a stated purpose or purposes and intended clients. They can be extremely large scale – perhaps with millions of potential clients – or just a few, but they are always used to do something useful to someone, somewhere.
ISs are also held together with some form of communications technology (e.g. Ethernet) and can be distributed over large geographical areas.