The profession of Mechanical Engineering, second largest among engineering disciplines, involves the design, analysis, and manufacturing of machines. Central to the profession is the importance of innovation and creating new technologies and products. Mechanical engineers work in teams involved in designing jet engines; automobiles; aircrafts and spacecrafts; microelectromachanical acceleration and pressure sensors; heating, ventilation, and air conditioning systems; biomedical and biomechanical devices as artificial hip implants; and such integrated mechanical and electronic (mechatronic) systems as robots.Mechanical engineers are employed by small start-ups, multinational corporations, government agencies, national laboratories, consulting firms, and universities. They can work in areas of research, design, manufacturing, sales, quality assurance or management.