Mechanics is the branch of science concerned with the interaction of energy and forces with physical bodies, objects, and materials. In other words, it is the study of how things move, and it is part of the broader field of physics. Mechanics is important for understanding the design and operation of machines and tools, as well as the principles governing the actions of biological, astrological, and even atomic and subatomic systems.
Classical mechanics broadly encompasses the motion of macroscopic objects, and includes familiar concepts like momentum, gravity, and rotational motion. These principles are essential for mechanical engineering applications ranging from the creation of machines as simple as a wheelbarrow to cutting-edge robotics. These mechanics can also be used to describe human actions; for example, the way a baseball pitcher throws a curveball.
In recent decades, the field of quantum mechanics has emerged to explain motion of atoms and subatomic particles. Unlike classical mechanics, the principles governing these phenomena are not as obvious or intuitive as the macroscopic world we move through in our daily lives, and it has required enormous advances in science and technology to be able to conduct experiments to discover and understand these properties.‎