Linked from
The 14 pages that link to Curl, each with the reason it gives.
Vector fieldRelated: It identifies where the field circulates around a point.
GradientCompared with: Unlike the gradient, curl acts on vector fields and detects local rotation.
Conservative forceRelated: In a simply connected region, a zero-curl force field is conservative.
Stokes' theoremBroader topic: Stokes' theorem integrates this local rotation across the surface.
Vector calculusBroader topic: It quantifies the field's tendency to circulate around a point.