Basically the same as classical mechanics.
The idea tha taking the limit of the non-classical theories for certain parameters (relativity and quantum mechanics) should lead to the classical theory.
It appears that classical limit is only very strict for relativity. For quantum mechanics it is much more hand-wavy thing. See also: Subtle is the Lord by Abraham Pais (1982) page 55.
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Classical mechanics is a branch of physics that deals with the motion of objects and the forces that affect that motion. It describes the behavior of macroscopic objects, from everyday objects like cars and projectiles to celestial bodies like planets and stars, under the influence of various forces. Classical mechanics is primarily governed by Newton's laws of motion, which were formulated by Sir Isaac Newton in the 17th century.