Mechanical engineering is a branch of engineering that applies the principles of physics and materials science for the design, analysis, manufacturing, and maintenance of mechanical systems. Mechanical engineers design mechanical and thermal systems including machines, mechanical components, tools and engines. The work involves analysing problems related to the production and use of heat and mechanical power, and designing, building, testing and maintaining devices, machines and systems. This includes tasks like designing components and systems for applications like vehicles, manufacturing plants, heating and cooling systems, medical devices and more. Mechanical engineers use tools like computer-aided design (CAD) software and simulation models, and employ principles from various fields like materials science, engineering mechanics, thermodynamics and manufacturing. Today, mechanical engineering also involves optimization of designs for efficiency, reduced environmental impact, economy and sustainability.

Mechanical engineers work on a wide range of projects encompassing components, machines and mechanical systems. Their roles include performing technical analysis, design, testing, production and maintenance of equipment. They are employed across diverse industries like automotive, aerospace, manufacturing, energy and more.

Critical skills for mechanical engineers include technical knowledge of engineering principles, strong mathematical and analytical abilities, design and drafting expertise using CAD tools and good communication and teamwork skills. Creativity and innovative thinking are also important to design novel solutions to mechanical problems.

In summary, mechanical engineering is a broad and challenging field that combines creative design work with technical analysis and practical problem-solving skills.