ABSTRACT
In Chapter 2 we developed the general theory of hyperidentities. As often hap pens, the development of this subject has involved an interplay between the general theory and specific examples; our knowledge of hyperidentities for spe cific algebras has suggested new directions for the theory, and vice versa. In this chapter we present results about hyperidentities for type (2) algebras, and in particular for varieties of semigroups.
