The main sources of Muslim law are the Quran and Sunnah (the practices and traditions of the Prophet Muhammad). Additional sources that developed are ijma (consensus of opinion among Islamic scholars) and qiyas (analogical reasoning following Muhammad's teachings). As Muslim society progressed, four main schools of Islamic law emerged - Hanafi, Maliki, Shafi, and Hanbali. During Muslim rule in India, personal laws applied only to Muslims, while secular civil laws applied to both Muslims and non-Muslims. Non-Muslims followed their own religious laws, while criminal laws dealing with universally condemned crimes applied to both groups.