Arab tradition, similar to other tribal cultures of that time, was to name things according to their unique characteristics. They used this same method to name Quranic chapters. Most chapter names are found in hadith. Some were named according to their central theme, such as "Al-Fatiha" (The Opening) and "Yusuf" (Joseph), and some were named for the first word at the beginning of the chapter, such as "Qaf", "Ya-Sin", and "ar-Rahman". Some "surahs" were also named according to a unique word that occurs in the chapter, such as "al-Baqarah" (The Cow), "An-Nur" (The Light), al-Nahl (The Bee), "Az-Zukhruf" (The Ornaments of Gold), "Al-Hadid" (The Iron), and "Al-Ma'un" (The Small Kindness).