Mechanical engineering is the discipline that applies engineering, physics, engineering mathematics, and materials science principles to design, analyze, manufacture, and maintain mechanical systems. It is one of the oldest and broadest of the engineering disciplines.The mechanical engineering field requires an understanding of core areas including mechanics, dynamics, thermodynamics, materials science, structural analysis, and electricity. In addition to these core principles, mechanical engineers use tools such as computer-aided design (CAD), computer-aided manufacturing (CAM), and product life cycle management to design and analyze manufacturing plants, industrial equipment and machinery, heating and cooling systems, transport systems, aircraft, watercraft, robotics, medical devices, weapons, and others. It is the branch of engineering that involves the design, production, and operation of machinery.[1][2]Mechanical engineering emerged as a field during the Industrial Revolution in Europe in the 18th century; however, its development can be traced back several thousand years around the world. In the 19th century, developments in physics led to the development of mechanical engineering science. The field has continually evolved to incorporate advancements; today mechanical engineers are pursuing developments in such areas as composites, mechatronics, and nanotechnology. It also overlaps with aerospace engineering, metallurgical engineering, civil engineering, electrical engineering, manufacturing engineering, chemical engineering, industrial engineering, and other engineering disciplines to varying amounts. Mechanical engineers may also work in the field of biomedical engineering, specifically with biomechanics, transport phenomena, biomechatronics, bionanotechnology, and modelling of biological systems.

機械工程是應用工程、物理、工程數學和材料科學原理來設計、分析、制造和維護機械系統的學科。它是最古老和最廣泛的工程學科之一。機械工程領域需要了解核心領域，包括力學、動力學、熱力學、材料科學、結構分析和電學。除了這些核心原則，機械工程師還使用計算機輔助設計(CAD)、計算機輔助制造(CAM)和產品生命周期管理等工具來設計和分析制造工廠、工業設備和機械、加熱和冷卻系統、運輸系統、飛機、船舶、機器人、醫療設備、武器等。它是工程的一個分支，涉及機械的設計、生產和操作。機械工程是18世紀歐洲工業革命中出現的一個領域，但其發展可以追溯到幾千年前的世界各地。19世紀，物理學的發展導致了機械工程科學的發展。該領域不斷發展，不斷融合先進技術；如今，機械工程師正在尋求復合材料、機電一體化和納米技術等領域的發展。它還與航空航天工程、冶金工程、土木工程、電氣工程、制造工程、化學工程、工業工程和其他工程學科有不同程度的重疊。機械工程師也可以在生物醫學工程領域工作，特別是在生物力學、運輸現象、生物統計學、生物納米技術和生物系統建模方面。