  The notion of temperature in many body elementary particle processes is in a
common use for decades. Thermal models have become simple and universal
effective tools to describe particle production -- not only in high energy
heavy ion collisions but also in high energy elementary particle collisions. We
perform a critical analysis of the temperature concepts in such processes.
Although the temperature concept is a very useful tool, nevertheless it should
be used with the care, taking into account that usually it is just model
dependent fitted parameter.
