A fatwa is a legal ruling on a point of Islamic law given by a qualified Faqih (Islamic jurist) in response to a question posed by a private individual, judge, or government. The word fatwa comes from the Arabic root f-t-w, which means "youth, newness, clarification, explanation". A jurist issuing fatwas is called a mufti, and the person who asks for a fatwa is known as mustafti. The act of issuing fatwas is called iftāʾ, and the term futyā refers to soliciting and issuing fatwas.

Fatwas are usually issued in response to questions from individuals or Islamic courts, and they offer a picture of the projects, wants, and fears of Muslim individuals and communities. They are authoritative but are generally not treated as binding judgments, and a requester who finds a fatwa unconvincing is permitted to seek another opinion. Fatwas can be requested when a Muslim, confronted with a problem of life, belief, or law, is unsure what to do, and they may be issued in response to a given situation.

While fatwas often begin with a request by a Muslim layperson, they may be issued in response to a given situation. Examples include the fatwa issued by Dar al-Ulum Deoband in 2010 against terrorist organizations like the Islamic State because they were judged to be not Islamic, and the fatwa issued by the Indonesian Council of Ulama in 2014.

It is important to note that given wide media coverage of the fatwa against Salman Rushdie, some may conclude that a fatwa always means a death sentence. However, a fatwa rarely calls for death, can be issued by a variety of religious authorities, and is mostly of interest to a particular Muslim individual or community.