"Ismah" is the concept of infallibility or "divinely bestowed freedom from error and sin" in Islam. Muslims believe that Muhammad and other prophets in Islam possessed "ismah". Twelver and Ismaili Shia Muslims also attribute the quality to Imams as well as to Fatimah, daughter of Muhammad, in contrast to the Zaidi, who do not attribute 'ismah to the Imams. Though initially beginning as a political movement, infallibility and sinlessness of the imams later evolved as a distinct belief of (non-Zaidi) Shiism.