F4 Wiki:Start Here

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GD&T Reference Standard definitions, symbols, and usage guidance.

F4 Behavior How the F4 validator interprets and checks GD&T.

Glossary Short definitions and quick references.

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Form Straightness Flatness Circularity Cylindricity	Orientation Parallelism Perpendicularity Angularity
Location Position Position (Composite) Position (MSS) Concentricity Symmetry	Profile Profile of a Line Profile of a Surface Profile (Composite) Profile (MSS)
Runout Circular Runout Total Runout	Supporting topics Modifiers Datums Examples

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