Event-by-event fluctuations

The physics of event by event fluctuations in heavy ion collisions is discussed. It is argued that fluctuations are indeed a new tool to investigate the properties of the matter created in these conditions. An example is given to show how charge fluctuations can be utilized to detect the presence of a quark gluon plasma. It is indicated that the measurement of momentum fluctuations can give an idea about the heat capacity of the systems