According to ABET, or the Accreditation Board for Engineering and Technology: "Engineering is the profession in which a knowledge of the mathematical and natural sciences, gained by study, experience, and practice, is applied with judgment to develop ways to utilize, economically, the materials and forces of nature for the benefit of humankind." There is considerable overlap between science and engineering. Research teams often consist of one or more engineers who work closely with scientists to design and build some of the tools required for lab experiments or to test theories in practice. Engineers are motivated to improve our quality of life; here are some examples: making renewable energy economical, improving health informatics, making better medicines, improving automobile safety, and improving urban infrastructure. Engineers typically develop new products using several steps - Design phase, testing, production and maintenance. During the design phase, engineers specify the functional requirements; design and test the components; produce a prototype; and evaluate the overall effectiveness, cost, reliability, and safety. This process is common in the development of many different products such as chemicals, computers, energy sources, and transportation. During testing, production and maintenance, engineers determine if any failures of the components are likely and where they occur. This is where they estimate the time and cost required to produce a product. In these processes, engineers use computers to create designs, analyze functionality, and simulate how a machine, structure, or system operates.