IDEF is an acronym meaning ICAM DEFinition, where ICAM is an acronym for Integrated Computer Aided Manufacturing. Developed by the US Air Force, IDEF is a commonly used approach for Computer Integrated Manufacturing Systems design. IDEF0 is closely related to SADT (Structured Analysis and Design Technique), a graphical language which predates IDEF0.
The basic components of IDEF are a box and arrows:
• Controls - Specifies the conditions required for the function to produce correct outputs.
• Inputs – Something that is transformed or consumed by the function
• Outputs – Data or objects produced by the function
• Mechanism – Means that support the execution of the function
• Call – Support information provided to other functions
• Function name shall be an active verb or phase (process parts, design system, …)
• Arrows identify data or objects needed or produced by the function and are labeled with a noun or noun phrase (specifications, budget, design engineer, …)
Note that IDEF3 and IDEF5 are Descriptive, while the rest are used to build a Model. IDEF1x was added later to address databases (also called Entity Relationship Diagrams).