9. Conclusions

In this paper we have recalled some methods used to study subgroups of groups and compared them in terms of prefix string rewriting. A procedure based on prefix string rewriting was presented which emulates Todd-Coxeter coset enumeration naturally hence bringing TC and string rewriting into a much closer context. This procedure was generalized to the setting of monoids where it is related to the more general concept of blocks as introduced by Neumann in [12].