http://www.articleheaven.net en-us editorial@articlealley.com Audio book classified into three category such as audio book on tape, audio book on CD and audio book MP3. The first audio book is audio book on tape and on 1980's this kind of audio book become so popular. That made audio book improved. And these are s... http://www.articleheaven.net/seven-benefits-of-used-audio-book-1404731.html 18th February 2010