The Arabic word hadith literally means “story.” As used in Islam, the Hadith are stories about the prophet Muhammad (d. 632), the founder of Islam. The Hadith report the Sunna, or practices of Muhammad, including what he said, what he did, and what he tacitly approved of. Each Hadith has two parts: the text reporting Muhammad's words and actions, called matn in Arabic, and the chain of narrators, or isnad. The chain of narrators begins with the narrator from whom the compiler of a collection of Hadith received the report and is traced back through the generations, ending with the narrator who reported witnessing what Muhammad said or did. Each person in the chain of narrators reports the story on the authority of the person from whom he or she received it. The Arabic word sahih means “sound,” and the book of Hadith known as the Sahih al-Bukhari was an attempt to collect only those stories that the compiler considered to be sound, or authentic—;that is, stories that he viewed as reliable because they could be traced back to Muhammad through an unbroken chain of trustworthy narrators.