The emphasis throughout is unashamedly on what might be called 'pure' semigroup theory; the inclusion of significant amount of application, for example, to automata, languages and machines, would have involved a huge, and probably unacceptable, increase in the length (and the price) of the book. The only mild genuflection in the direction of applied semigroup theory occurs in Chapter 7, where the brief section on variable length codes gives some hint a fascinating and continually developing field.

• 1: Introductory ideas


• 2: Green's equivalences; regular semigroups


• 3: 0-simple semigroups


• 4: Completely regular semigroups


• 5: Inverse semigroups


• 6: Other classes of regular semigroups


• 7: Free semigroups


• 8: Semigroup amalgams


• References


• List of symbols