The Arabic word hadith literally means speech and also new: because speech is created as it is uttered, it is always new. Following the Prophet Muhammad's death (632 CE), people engaged in speech about him so much that the word hadith was eventually reserved for speech related to the Prophet............. Download the full article in pdf attachment (below)

a 7,000 word Article, The Encyclopedia of Religion, New York: Macmillan Publishing Co., 2005.