EBooks are electronic books which can be downloaded from any website or FTP site on the Internet. EBooks are made using special software and can include a wide variety of media such as HTML, graphics, Flash animation and video.
As a rule of thumb you should remember that almost anything that can be displayed or listened to on the Internet can be packaged into an eBook. This means that an eBook can be interactive and can be very visually pleasing. This can be done without worrying about download times as once the eBook is downloaded the first time all the media and associated files are stored on the user's computer.
What's also great about eBooks is the fact they can be updated with the click of a button so the user always has the most current version on his or her desktop.
Marketing with eBooks

Using eBooks when marketing and promoting your site or affiliate program can be a very powerful method, especially with free eBooks.
Let's say you wrote an eBook on your subject and offered it free on your website, people love free things and especially love free information about a topic they're interested in so they will download it.
Included in your eBook you're going to have links back to your website, product or affiliate program, since the eBook is on the users computer they'll have permanent access to it, if it's a good eBook with lots of information and one that you regularly update they'll use your eBook again and again constantly seeing a link or banner which directs them to your site.
The more of your website visitors that download your free eBook the more free exposure and repeat visitors you'll get.
The real power behind eBook marketing however is the viral aspect of it. Imagine that you post a little message inside your eBook and on your website saying that other webmasters can give away the free eBook too on their sites; they'll love this as it'll attract visitors and add value to their sites. Again the more times their visitors download it the more exposure and free traffic you'll get.
There are also lots of eBook directories on the Internet where you can list your free eBook, so it's not unusual for a good eBook full of information to be downloaded 10,000 times. This means every time one of the users read it they'll think of your website and see your banner or link. Using eBooks truly is a great way to get lots of free traffic in a short amount of time and to constantly have your message in front of lots of people.