An architectural drawing depicts a building project and is used by architects for various purposes. There are several stages of an architectural project including a project brief, schematic design, design development, and construction. A project brief outlines the client's requirements and forms the basis for appointing an architect. Sketches are rapidly executed drawings used to develop and communicate rough design ideas. Schematic design diagrams and preliminary drawings are used to explore spatial relationships and design concepts. Construction drawings along with specifications and estimates comprise the final design requirements.