Point particle

From Freepedia

A point particle is an idealized particle heavily used in physics. Its distinguishing features are that it does not have any volume or surface area; it is zero dimensional. A point particle is often a good approximation of real particles and also more extended bodies. In Newtonian gravitation as well as General relativity and Electromagnetism, the respective fields produced by spherical objects and point particles of equal charge/mass are equal outside of the spherical object.