A bar code checkout system at a grocery store that is used to gather sales information.

IT$+$Business$+$People $$

Excel "what if$"$ spreadsheet models used by management to simulate different semi$-$ structured or unstructured scenarios related to applications such as demand forecasting and capacity planning. These systems require some user interaction and human judgment.

A system that applies knowledge and reasoning $($and an "inference engine"$)$ to help diagnose or solve a problem. An example of this could be a DELL employee troubleshooting some computer hardware problem for a customer over the phone using a database and software based on $"$IF$..$THEN" rules.