The term "Twelver" refers to a branch of Shia Islam that believes in a succession of twelve Imams as the rightful leaders of the Muslim community. These Imams are considered to be divinely appointed and infallible, with the twelfth Imam, Muhammad al-Mahdi, believed to be in occultation and will return as a messianic figure. Twelvers, also known as Ithna Ashari, emphasize the importance of following the teachings and guidance of these Imams. They celebrate various religious observances, including Ashura, which commemorates the martyrdom of Imam Hussein, the third Imam, and is a significant event in their faith.