This requires a purposeful abstraction of reality and the implementation of the resulting concept to make it executable on computers. These processes are better known as “modeling,” the purposeful abstraction of reality and capturing of assumptions and constraints, and “simulation,” the execution of a model on a computer. Modeling & simulation (M&S) becomes more and more a backbone of operational research to cope with highly complex and dynamic environments and decision challenges that are often illor semi-structured in nature, in particular when such M&S systems utilize knowledge management and agent directed simulation to enable intelligent decision technologies, such as agent mediated decision support.
The defining characteristic of composability is the ability to combine and recombine components into different simulation systems for different purposes. - Petty and Weisel
I'm very interested the Interoperability of Systems at different levels-of-detail. As more of the real world is modeled in software, we are forced to understand how systems integrate on a holistic level. Micro to macro.