Prism is a solid geometrical figure whose two ends are similar, equal and parallel rectilinear figures and whose sides and faces are either parallelograms or rectangles. It has 3 faces,9 edges, and 6 vertices. Prism is a solid whose side faces are ||gm and whose end basses are two parallel and congruent polygons—recognition of Solids. You come across many solids every day. The football that you play, the book that you read, the LPG cylinder used for cooking and so on are all solids. Unlike 2D shapes, a solid has length, breadth and depth. Solid figures are three-dimensional objects, meaning they have length, width, and height. Because they have three dimensions, they have depth and take up space in our universe. Chapter 31 deals with the study of essential concepts such as identification of 3D shapes and nets, which can be used to form cubes.