Design is intelligence made visibleA design is a plan or specification for the construction of an object or system or for the implementation of an activity or process, or the result of that plan or specification in the form of a prototype, product or process. The verb to design expresses the process of developing a design. In some cases, the direct construction of an object without an explicit prior plan may also be considered to be a design activity. The design usually has to satisfy certain goals and constraints, may take into account aesthetic, functional, economic, or socio-political considerations, and is expected to interact with a certain environment. Major examples of designs include architectural blueprints, engineering drawings, business processes, circuit diagrams, and sewing patterns." Everything is designed. Few things are designed well. "-- Brian Reed, front-end developer and musicianThe person who produces a design is called a designer, which is a term generally used for people who work professionally in one of the various design areas—usually specifying which area is being dealt with or interior designer), but also others such as architects and engineers. A designer's sequence of activities is called a design process, possibly using design methods. The process of creating a design can be brief or lengthy and complicated, involving considerable research, negotiation, reflection, modeling, interactive adjustment and re-design.Design as a processSubstantial disagreement exists concerning how designers in many fields, whether amateur or professional, alone or in teams, produce designs. Kees Dorst and Judith Dijkhuis, both designers themselves, argued that "there are many ways of describing design processes" and discussed "two basic and fundamentally different ways", both of which have several names. The prevailing view has been called "the rational model", an American scientist, and Gerhard Pahl and Wolfgang Beitz, two German engineering design theorists. It posits that:Designers attempt to optimize a design candidate for known constraints and objectives.The design process is plan-driven.The design process is understood in terms of a discrete sequence of stages.The rational model is based on a rationalist philosophy According to the rationalist philosophy, design is informed by research and knowledge in a predictable and controlled manner.Example sequence of stagesTypical stages consistent with the rational model include the following:Pre-production designDesign brief or Parti pris – an early statement of design goalsAnalysis – analysis of current design goalsResearch – investigating similar design solutions in the field or related topicsSpecification – specifying requirements of a design solution for a product or service.Problem solving – conceptualizing and documenting design solutionsPresentation – presenting design solutionsDesign during productionDevelopment – continuation and improvement of a designed solutionTesting – in situ testing of a designed solutionPost-production design feedback for future designsImplementation – introducing the designed solution into the environmentEvaluation and conclusion – summary of process and results, including constructive criticism and suggestions for future improvements