Hanbali is one of the four schools of Fiqh or religious law within Sunni Islam. It is considered to be the most conservative of the four schools. The school was started by the students of Imam Hanbal. Hanbali is predominant among Muslims in the Arabian Peninsula, although students of Islam throughout the world study and may choose to observe its conclusions about Islamic practise. Hanbali is followed by less than 5% of the world's Muslim population. The Hanbali school was greatly supported by Muhammad ibn abd al-Wahhab who used this system of fiqh. It is thus the school of jurisprudence used in modern day Saudi Arabia.