"Tafsir" is a branch of knowledge that involves the discussion of various aspects of Quranic verses, such as the circumstances of revelation (Asbab al-Nuzul), the classification of verses into Makkan and Madani, distinguishing between clear and allegorical verses (Muhkam and Mutashabih), abrogating and abrogated verses (Naskh), specific and general verses (Khas and Am), absolute and qualified commands (Mujmal and Mufassal), permissible and forbidden matters (Halal and Haram), promises and threats, commands and prohibitions (Amr and Nahy), lessons and examples, and so on.