The Twelve Imams

The Twelve Imams (, '; , ') are leaders and the sucessors of Prophet Muhammad for the Twelver branch of Shī‘ah Islam.
According to Twelver Shia Muslims these twelve guiders are authorized by Allah for the guidance of Muslims and for protection of Islam and they are infallible (sinless). It is said by Twelver Shia Muslims that the Twelve Imams were foretold in the in the sayings of Muhammad.
It is believed by Twelver Shia Muslims that these Imams have the knowledge of each and every thing which is told them by God. Ali was the first Imam of this line every Imam was the son of the previous Imam, except Husayn ibn Ali who was the brother of Hasan ibn Ali. The last Imam is Imam al-Mahdi, who is alive and will appear in the end times.