Joanne "Jo" Rowling OBE is an English fiction writer who writes under the pen name J. K. Rowling. Rowling is the author of the Harry Potter fantasy series, which has gained international attention, won multiple awards, and sold over 325 million copies worldwide. In February 2004, Forbes magazine estimated her fortune at £576 million (just over US$1 billion and still is at the same spot in 2007), making her the first person to become a US-dollar billionaire by writing books. In 2006, Forbes named her the second richest female entertainer in the world, behind talk show host Oprah Winfrey.