Councils can choose between two ways in which an election can be run, ‘first past the post’ (FPTP) or the Single Transferable Vote (STV).
Gall cynghorau ddewis o blith dwy ffordd o gynnal etholiad, sef 'y cyntaf i'r felin' (FPTP) neu'r bleidlais sengl drosglwyddadwy (STV).