This document provides an overview of various Islamic sects and schools of thought, including their key beliefs and differences. It discusses the Kharijites, Sunnis (including the Salafi, Ash'ari, and Maturidi schools), Shi'ites (Zaydi, Imamiya, Ismaili, and Nusayri branches), Mu'tazila, and Ahmadiyya movement. It also outlines some of the theological problems and points of disagreement between the different Islamic schools, such as issues relating to God, prophethood, the afterlife, human nature, and leadership.