An IFC entity, often called an IFC class, is a definition in the IFC schema: IfcWall, IfcSlab, IfcDoor, IfcDuctSegment, IfcSpace and hundreds more. Each exported element is an instance of one entity.
Many entities have a predefined type for more precision, for example IfcSlab with type FLOOR, ROOF or LANDING. Choosing the correct entity is what lets checkers, viewers and quantity tools treat elements correctly.
Discussion
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