The document discusses concepts in solid geometry including: - Classifying three-dimensional figures according to their properties such as polyhedra, prisms, pyramids, cylinders, and cones. - Relating two-dimensional nets to their three-dimensional shapes. - Analyzing cross-sections of three-dimensional shapes. - Key terms such as faces, edges, vertices, altitude, Platonic solids, Euler's formula, and surface area are defined. - Examples of describing three-dimensional shapes from their nets and calculating surface areas of prisms are provided.