Gravitation is the physical phenomenon of mutual attraction of massive bodies.
In the context of modern physics, gravitation is described by Einstein's Theory of General Relativity in terms of the curvature of the space-time continuum. General Relativity allows the description of problems in the presence of strong gravitational fields. A rigorous discussion of General Relativity uses advanced mathematical concepts from Differential Geometry and Tensor Calculus.
In the special case of weak gravitational fields, such as the field near the surface of the Earth, Newton's Law of Gravitation (Principia, 1687) is sufficient for the accurate description of a wide range of physical phenomena. Many of those phenomena are the subject of homework and exam problems in introductory physics courses, for example: