Scheme drawing: The preliminary design is just a sketch of the final product. In the preliminary design, accurate data, reliable structure and accurate drawings are not required. Some are just a sketch.

　　Processing drawing: In the deepening design stage of the drawing, the original design will be refined. At this time, the drawing includes the layout, nodes and other structures, as well as the processing drawing.

　　Construction drawing: The construction drawing is a drawing showing the overall layout of the project, the external shape of the building, internal layout, structural structure, internal and external decoration, material practices and construction requirements. The construction drawing has the characteristics of complete drawings, accurate expression and specific requirements. It is the basis for engineering construction, preparation of construction budget, construction organization design, and is also an important technical document for technical management. A complete set of construction drawings, generally including construction drawings, structural construction drawings, water supply and drainage, heating and ventilation construction drawings and electrical construction drawings and other professional drawings.