From ACT Wiki
1. Modelling - relationships - non-linear - complex problems - contrasted with merely complicated problems.
Strictly, complex systems and problems - contrasted with merely complicated ones - consist of both:
- A large number of interacting elements; and
- Non-linear and unpredictable relationships between the interacting elements, making the system impossible to model reliably using traditional techniques.
More loosely, the same as complicated.
Any group or system of things that are linked closely, or in a complicated way.