  Gravitational N-body simulations, that is numerical solutions of the
equations of motions for N particles interacting gravitationally, are widely
used tools in astrophysics, with applications from few body or solar system
like systems all the way up to galactic and cosmological scales. In this
article we present a summary review of the field highlighting the main methods
for N-body simulations and the astrophysical context in which they are usually
applied.
