Develop and sell digital books can be very profitable if you manage to find a niche market with a purchasing power that are interesting and google tools that will help you verify whether or not a market for what you sell, but this is tied to the quality of your page landing or sale, the quality of your product, your selling price and a campaign with Google AdWords and other free portals to promote your product and generate qualified traffic and make the sale, if you make things the right way can make money online selling your own digital product. SECOND ALTERNATIVE TO EARN MONEY ONLINE An alternative that many talk about is ClickBank products and many speak more than making money through clickbank no website because let me tell you that does not work, the tools that many speak so you can publish the product free of charge do not have much traffic, I consider them free options to generate traffic but not sales, today the least known of internet you can differentiate an article, a blog, social networking, website and free web pages and when one works with the free tools do not give it veracity of what they offer, such as your you buy a product if you see it in an article or blog that only put the link of the product and do not say anything about it, or if say some of the product are comments without proof, if you want to generate revenue and make money in this way the answer is yes you can pear as well as your digital book going to have to work to find the ideal product for the market they want to sell, you should actually buy the product if you want to build credibility and create a web page with your own domain to give seriousness of what you offer, so the reader knows your website you actually try the product and recommend it in honestly and seriously. .