A game engine is:
- technology
- methodology
- platform
- business
- tool
- foundation
- bundle of software engineering idioms
Other than Organizational / Social / Product.
- graphics
- physics
- networking
- artificial intelligence
- monetization
- asset libraries and importing
- user interface libraries
- platform support
- tools
- Unity
- Unreal Engine
- id Tech 7
- Iron Engine
- Creation Engine
- Jedi
- Luminous Studio
- CryEngine
- Riot Engine
- Source 2
- StepMania
- Aurora Toolset
- Clausewitz
- Forgelight Engine