[...] the statistical properties of laser light change qualitatively at the laser threshold. Below laser threshold noise increases more and more while above threshold it decreases again. [...] Below laser threshold, light consists of individual wave tracks which are emitted from the individual atoms independently of each other. Above laser threshold, a practically infinitely long wave track is produced. In order to make contact with other processes of self-organization let us interpret the processes in a lamp or in a laser by means of Bohr's model of the atom. A lamp produces its light in such a way that the excited electrons of the atoms make their transitions from the outer orbit to the inner orbit entirely independently of each other. On the other hand, the properties of laser light can be understood only if we assume that the transitions of the individual electrons occur in a correlated fashion. [...] Above laser threshold the coherent field grows more and more and it can slave the degrees of freedom of the dipole moments and of the inversion. Within synergetics it has turned out that is a quite typical equation describing effects of self-organization. [...] This equation tells us that the amplitude of the dipoles, which is proportional to A, is instantaneously given by the field amplitude B(t) (and by the fluctuating force). This is probably the simplest example of a principle which has turned out to be of fundamental importance in synergetics and which is called the slaving principle.