Linked from
The 14 pages that link to Winding number, each with the reason it gives.
Fundamental groupBroader topic: For the circle, it identifies loop classes with integers.
Complex logarithmRelated: Each winding around zero changes a continued logarithm by \(2\pi i\).
Contour integrationRelated: It weights each enclosed singularity in the residue theorem.
Closed curveRelated: It records a loop’s turning around points not on the curve.
Star polygonRelated: It helps describe how a self-intersecting star outline loops around its center.