Haram is an Islamic concept which has been extensively used in Quran and hadith and means forbidden, impermissible, or unlawful. Opposite of haram is halal which means permissible, lawful, and legal. The Quran and hadith use the word haram in three different connotations: first, haram in matters of faith or belief; second, haram from moral perspective; and third, haram in material sense. Usually in Islamic theology, haram and sin are used in synonyms and interchangeable terms. The concept of haram in Islam is different from illegal in west as something may be considered legal from constitutional perspective while still being prohibited from religious or Islamic perspective. To declare something haram, one has to produce a convincing argument and evidence from Quran or hadith. The principle established by scholars regarding haram is that everything termed as clean or chaste, should be considered halal unless proven to be otherwise, either in the light of Quran or hadith.