Book Industry Standards and Communications (BISAC) categories are used by the book-selling industry to help identify and group books by their subject matter. Choose one BISAC category that best fits your book. To find a complete guide of BISAC categories click on the link below. This is the most currently list available. The BISAC Category Code will be required to publish your paperback book. For Kindle you will be asked to choose two Book Categories from a slightly different list.