Product design is the process of creating new products to sell to customers. It involves efficiently generating and developing ideas through a process that leads to new products. Key steps in product design include idea generation, concept screening, competitive analysis, concept testing, in-depth analysis, prototype development, and commercialization. An example is the design process for the iPhone, which involved estimating manufacturing and operating costs, developing resistive and capacitive touchscreen technologies, and generating over $150 million in profits from initial sales despite $150 million in research and development costs.