Sunnah, Sunnah

In the context of Islamic Law, Imam Malik and the Hanafi scholars assumed to have differentiated between the sunna and the hadith. In some instances, for example, Imam Malik is supposed to have rejected hadiths that reached him because, according to him, they were against the 'established practice of the people of Medinah'. According to other opinions, sunnah constitutes of what Muhammad believed, implied or tacitly approved and was noted down by his companions in form of what is today known as hadith. In Shi'a Islam, the word "Sunnah" means the deeds, sayings and approvals of Muhammad and the twelve Imams who Shi'a Muslims believe were chosen by Muhammad to lead the Ummah - the world Muslim community.

Source: Wikipedia > Sunnah