Someone please correct me if I'm wrong, but isn't Ifa the religion. Yoruba is the name for the people/ethnic group as the other poster responded. Also, in the America's Ifa, along with combinations of other traditional African religions served as survival religions for slaves. They would disguise their African Deities through the Catholic Saints which is why many people continued and still continue to claim both religions. For example, it has been reported that as many as 15 percent of people in New Orleans still practice Vodun or Voodoo today but they are also practicing Catholics.