Malachi or Mal'achi was a prophet in the Bible, the Christian Old Testament and Jewish Tanakh. He was the first of the minor prophets, and the writer of the Book of Malachi, the last book of the Old Testament canon (Mal. 4:4, 5, 6) Christian editions, and is the last book of the Neviim (prophets) section in the Jewish Tanakh. No allusion is made to him by Ezra, however, and he does not directly mention the restoration of the temple. Wikipedia
The definitive Wikipedia entry for Malachi. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Malachi