力学是物理学的一个分支，主要研究能量和力以及它们与物体的平衡、变形或运动的关系。

人们在日常劳动中使用杠杆、打水器具等等，逐渐认识物体受力，及平衡的情况。古希腊时代阿基米德曾对杠杆平衡、物体重心位置、物体在水中受到的浮力等，作了系统研究，确定它们的基本规律，初步奠定了静力学，即平衡理论的基础。

自文艺复兴之后，科学革命兴起，伽利略的自由落体运动规律，以及牛顿的运动定律皆奠定了动力学的基础。力学从此开始成为一门科学。此后弹性力学和流体力学基本方程的创建，使得力学逐渐脱离物理学而成为独立学科。到20世纪初，在流体力学和固体力学中，实际应用跟数学理论的互相结合，使力学蓬勃起来，创立了许多新理论，同时也解决了工程技术中大量关键性问题。

Mechanics (Greek μηχανική) is an area of science concerned with the behavior of physical bodies when subjected to forces or displacements, and the subsequent effects of the bodies on their environment. The scientific discipline has its origins in Ancient Greece with the writings of Aristotle and Archimedes (see History of classical mechanics and Timeline of classical mechanics). During the early modern period, scientists such as Khayaam, Galileo, Kepler, and Newton, laid the foundation for what is now known as classical mechanics. It is a branch of classical physics that deals with particles that are either at rest or are moving with velocities significantly less than the speed of light. It can also be defined as a branch of science which deals with the motion of and forces on objects.