The "Twelve Imams" are a series of spiritual leaders in Shia Islam, believed to be the rightful successors to the Prophet Muhammad. They are considered infallible and divinely appointed, guiding the Muslim community in matters of faith and practice. The first Imam is Ali ibn Abi Talib, the cousin and son-in-law of Muhammad, followed by eleven others, culminating with the twelfth Imam, Muhammad al-Mahdi, who is believed to be in occultation and will return as a messianic figure. Each Imam is revered for their knowledge, piety, and leadership, playing a crucial role in shaping Shia beliefs and practices. The Twelve Imams are central to the identity of Twelver Shia Islam, the largest branch of Shia Muslims, who commemorate their lives and teachings through various religious observances and rituals.