Smashwords is the worlds largest distributor of independently published ebooks. To publish your book on Smashwords, you need to follow really closely their detailed criteria, but if successful, your book will be listed on the Premium catalogue. This opens your book to wider global retailers than the Standard catalogue which has a more limited retailer base.
Whereas Amazon only gives a limited sample preview to readers, you as an author get to decide how much of your book can be sampled before purchase on Smashwords.
Where does Smashwords Distribute?
Your book is available for distribution as an ebook to Amazon Kindle, Apple, Barnes and Noble, WH Smith (which we are more familiar with in Ireland and UK) in addition to global online ebook retailers such as Scribd, Oyster, Kobo, Overdrive, Flipkart, Baker and Taylor and Inktera (formerly called Page Foundry).
You may be asking why publish on Amazon kindle when you can do it through Smashwords. Personally I prefer to convert my own Kindle book and upload to Amazon so I have 100% control over what it looks like.
If you really are interested in having an online presence and are not as interested in seeing your book in print and want to keep costs low, Smashwords is an affordable option for getting your book online.