There is no clear distinction between "serious simulations" and "physics engines", it's just that "physics engine" have a "for video game" connotation.
And especially, in the context of gaming, it usually means "rigid body dynamics simulation" in particular.
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Simulation software is a type of computer program designed to imitate real-world processes, systems, or environments. It allows users to create models that replicate the dynamics and behaviors of various entities, which can be anything from physical objects and biological processes to complex systems like financial markets or logistics networks. Here are some key features and purposes of simulation software: 1. **Modeling**: Users can create detailed models of the systems they wish to study.