This directories are splitted into different categories for Assembly Definitions.
You can use Assembly Definitions to speed up compilation time.
Import .unitypackage FImpossible Assembly Definitions to have them prepared automatically.


/Editor - Scripts responsible for drawing inspector windows and other gui for plugins
and also additional editor menus

/Plugins - Animating - All plugins related to animation or procedural animation grouped in one directory
/Plugins - Audio - All plugins related to Audio grouped in one directory
/Plugins - Level Design - All plugins related to level design grouped in one directory
/Plugins - Other - All plugins related to other things like optimization grouped in one directory
/Plugins - Shared - Demos plugins or my other free packages used in shared way for rest of the packages
/Shared Tools - Shared tools for inspector windows or shared math logics