Not necessarily! Both ganache and fondant are different types of frosting too. Ganache can be used instead of buttercream but fondant is rolled like a dough and needs to be used in combination with buttercream or ganache. Frostings have to be used at a spreadable consistency similar to peanut butter but fondant is like a dough and needs to be rolled with a rolling pin. Then draped over a cake for a smooth finish. It is a very impressive frosting that has endless possibilities.