Fallacious yet widespread and documented beliefs courtesy of Wikipedia.
The forbidden fruit mentioned in the Book of Genesis is commonly assumed to be an apple, and is widely depicted as such in Western art, although the Bible does not identify what type of fruit it is. The original Hebrew texts mention only tree and fruit. Early Latin translations use the word mali, which can be taken to mean both "evil" and "apple". German and French artists commonly depict the fruit as an apple from the 12th century onwards, and John Milton's Areopagitica from 1644 explicitly mentions the fruit as an apple. Jewish scholars suggested that the fruit could have been a grape, a fig, wheat, or etrog. Likewise, the Quran speaks only of a forbidden "tree" and does not identify the fruit.