This lecture covers topics related to surfaces and curvature in 3D modeling, including surfaces with zero curvature, variable curvature surfaces, and constant canonical curvatures. The instructor explains the development of surfaces, rules between lines and circles, and the quasi and non-developability of surfaces. The lecture also delves into the construction of surfaces between circles, hyperboloids, and cones, as well as the projection techniques and investigations in geometry. Various geometric concepts are explored through the analysis of different types of surfaces and their properties.