Mechanical engineering is a very broad field of engineering that involves the application of physical principles for analysis, design, manufacturing, and maintenance of mechanical systems. The system can be as simple as the design of a chair for comfort or as complex as the operations of a turbocharged engine for speed. It can be as small as the manufacturing of a nano-sized gear or as large as the structure of a supertanker used to carry oil around the world.

The major divisions of mechanical engineering are designs and controls, thermo-science and fluids, engineering mechanics, and manufacturing. Depending on the colleges and the universities, some mechanical engineering programs offer more specialized programs, such as mechatronics, robotics, transport and logistics, cryogenics, and biomechanics, if a separate department does not exist for these subjects.