In an assembly, there is an option to save these as new, permanently selectable display states as they are created. In a multi-body part, you only have the option to turn the temporary display state on and off. In either case, it allows a user to wade through the "visual noise" of components or bodies in the way of designing or analyzing a project throughout its design process.
Give it a try! The Isolate command is a great tool to add to your SolidWorks tool belt. Thanks for reading and happy designing!
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