Mechanical engineering develops mechanical systems and materials for public, commercial, and consumer markets. It is tremendously broad, spanning transportation, mechanisms, architecture, energy systems, materials, and more.

What are the detailed design features of the mechanical system that best satisfy the stated mission or market requirement? How will we conceive, design, implement, and operate mechanical components, products, and systems?

Mechanical engineers require experimental and computational data, legacy designs, regulatory requirements, market studies or mission need statements.

The conclusion of most mechanical engineering activity is a product ready for delivery to a customer, or integration into a larger system.

These concepts include materials science, stress, strain, loads, friction, dynamics, statics, thermodynamics, fluid mechanics, energy, work, CAD/CAM, machines, and so on.

Assumptions are in part shared by all scientists and engineers. One assumption is that the universe is controlled by pervasive laws that can be expressed in mathematical terms and formulas, and that those principles can be used to model mechanical systems. Mechanical engineers assume that market needs can be met with mechanisms and materials. Additionally, mechanical engineers frequently must integrate their work with other engineering disciplines (such as automotive, aerospace, electrical, computer, chemical, and so forth) in the design and implementation of a product.

Mechanical engineering products and services have wide-ranging implications that span global, national, and local economics, public infrastructure, transportation, health care and communications with potential for positive and negative quality of life impacts on communities and regions.

Commonly, the point of view is that of the design and manufacturing team. Other relevant points of view include the customer, stockholders, marketing, maintainers, or operators.