  Energy distributions of decay products carry information on the kinematics of
the decay in ways that are at the same time straightforward and quite hidden. I
will review these properties and discuss their early historical applications as
well as more recent ones in the context of i) methods for the measurement of
masses of new physics particle with semi-invisible decays, ii) the
characterization of Dark Matter particles produced at colliders, iii) precision
mass measurements of Standard Model particles, in particular of the top quark.
Finally I will give an outlook of further developments and applications of
energy peaks method for high energy physics at colliders and beyond.
