2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/101124We shall introduce the singular curvature function on cuspidal edges of surfaces, which is related to the Gauss-Bonnet formula and which characterizes the shape of cuspidal edges. Moreover, it is closely related to the behavior of the Gaussian curvature of a surface near cuspidal edges and swallowtails.30 pages with 6 figuresDifferential Geometry57R45; 53A05text