This document discusses different types of shapes used in interior design. It describes 2D and 3D shapes, positive and negative shapes, and some common geometric shapes used including squares, triangles, circles, and hexagons. Squares are easy to incorporate using side tables, mirrors, rugs, and cushions. Triangles create a dynamic feel when used in patterns. Circles are versatile, appearing in rugs, mirrors, and wallpaper. Hexagons are a bold choice for side tables, wall brackets, and coasters.