The direct sum of 2 copies of C_{2}. Or, if you will, the group of order 4 which is not a cyclic group. An Abelian group, on the 4 elements {*1,a,b,ab*}, defined by letting a and b commute, and requiring *a*^{2}=*b*^{2}=1. So, for instance, *ab***a*=*b*.