  The two defining features of the Einsteinian gravity are that it is self
interactive as well as it links universally to all particles including zero
mass particles. In the process of obtaining the Schwarzshild solution for
gravitational field of a mass point, we would demonstrate how are these
features incorporated? We would also show, unlike the Newtonian gravity, why
the gravitational potential in the Schwarzshild solution can have its zero only
at infinity and nowhere else;i.e. it is determined absolutely. We also consider
particle orbits to expose certain insightful and subtle points of concept and
principle.
