Mechanics is the branch of physics that deals with the behavior of physical objects that are subjected to forces or displacements. Classical Mechanics is the field of mechanics dealing with the physical laws that describe the motion of bodies under the action of a system of forces at every day sizes and velocities. Together thiso types of mechanics form the bases of physics.
Classical mechanics is limited in terms of the sizes and speeds at which it is applicable. The is because when the size of the objects gets extremely small quantum mechanics comes into play but on the macroscopic level quantum mechanics produces essentially the same results as classical mechanics. Further more when the speed of the objects gets extremely fast; that is approaching the speed of light relativistic mechanics comes into play while at the speed experienced in every day life relativistic mechanics produces essentially the same results as classical mechanics. Furthermore at larger scales of size and distance celestial mechanics come into play however this is actually just an expansion of the principles of classical mechanics to larger scales.
Classical Mechanics has an ancient history since the science goes back at least as far as ancient
with Greek philosophers like Aristotle. In practice the principles of
classical mechanics go back much further even though they were not yet
formulated. Classical Mechanics became a full fledged empirical science
starting with Galileo and then grew into the beginnings of physics as it is
known today with men like Isaac Newton. Greece
Classical mechanics has virtually unlimited applications particularly useful at the scales of size and speed of everyday life since those were the scales it was developed on. Every aspect of human life is affected by the application of force in one manner or another. Classical Mechanics is the foundation of physics because it is where physics had it start and where its main participles were laid down. Classical Mechanics works fine within our every day experience but reaches its limits when dealing with the very fast the very small.