Most councils agree in their constitutions to have more than one and the committees are usually organised around themes such as ‘children and young people’ or ‘the environment’.
Mae’r rhan fwyaf o gynghorau’n cytuno yn eu cyfansoddiad i gael mwy nag un, ac mae’r pwyllgorau fel arfer yn cael eu trefnu ar sail themâu fel ‘plant a phobl ifanc’ neu ‘yr amgylchedd’.