An ISBN number is the International Standard Book Number that uniquely identifies books and similar products that are published internationally. Beginning in 2007 it is now a 13 digit number that identifies your ebook title and your publishing company. In the case of an ebook you will be your own publisher. You can also purchase bar codes with your ISBN number embeddded. There are about 160 ISBN agencies throughout the world that assign these numbers.
There is a service fee charged when you get your ISBN numbers and they are generally sold in a group of 10 numbers. Having an ISBN number associated with your ebook will enable you to sell it on Amazon.com and through various other sources. Make sure you deal with a reputable broker when purchasing your ISBN’s so that the paperwork will be done correctly. It takes about two weeks to receive your block of numbers.