An antipope is a person who claims to be the pope but is not recognized as such by the mainstream Catholic Church. This situation typically arises during periods of schism, where there are competing claims to the papacy. Antipope claims can lead to confusion among the faithful and can create divisions within the Church. Historically, several antipopes have emerged, particularly during the Middle Ages. One notable example is Antipope Clement VII, who reigned during the Avignon Papacy when multiple popes were elected, leading to significant conflict and controversy within the Catholic Church.