Genetic algorithms rely on two genetic operators - crossover and mutaion. Although there exists a large body of conventional widsom concerning the roles of crossover and mutation, these roles have not been captured in a theoretical fashion. For example, it has never been theoretically shown that mutation is in some sense "less powerful" than crossover or vice versa. This paper provides some answer to these questions by theoretically demonstrating that there are some important characteristics of each operator that are not captured by the other.