**IDEF’s approach to Object-Oriented Design.** IDEF4 is a method for approaching Object-Oriented Design that was introduced alongside the other IDEF methods ([[IDEF]]). It’s not widely in use in its base form, but serves as a predecessor for things like [[UML]]. It contains many diagrams and datasheets.  Notably many of the diagrams logically contained under ‘Class Submodel’ are very similar to [[Class Diagrams]]. It also includes things like these:  And also [[State Diagrams]], like so:  Interestingly, [[Entity-Relationship Diagrams]] in IDEF4 use a Crow’s Notation, rather than the notation specified in [[IDEF1X]].  I don’t intend to ever learn much more about this method. I’ve scrolled through the IDEF4 spec. Good ‘nuff. **** # More ## Source - [IDEF4 - Object-Oriented Design Method - IDEF](https://www.idef.com/idef4-object-oriented-design-method/) ## Related - [[IDEF]] - [[Class Diagrams]] - [[Diagram Types (index)]]