In these notes we shall study algebras which are associated to blocks of tame representation type. These are the 2-blocks whose defect groups are dihedral or semidihedral or (generalized) quaternion. Over the last few years, a range of new results on a class of algebras including such blocks have been obtained. The algebras are essentially defined in terras of their stable Auslander-Reiten quivers (which we shall describe later), and it has been proved that any such algebra is Morita equivalent to one of the algebras in a small list which is explicitly given by generators and relations. In particular, this describes tame blocks; and allows one to extend classical results on the arithmetic properties of these blocks.