  We discuss the numerous advantages of using dimensionless equations in
non-relativistic quantum mechanics. Dimensionless equations are considerably
simpler and reveal the number of relevant parameters in the models. They are
less prone to round-off errors when applying numerical methods because all the
quantities are of the other of unity. A dimensionless equation facilitates the
application of perturbation theory and provides a glimpse of the sort of
solution we are going to obtain beforehand.
