EBooks is a digital version of a book that you can put onto devices such as your iPad, iPod and mobile but you would need a software on your device to view ebook’s like Aldiko, kobo and calibre that you can download from iTunes. To get an ebook you could either go to amazon or gutenburg. On amazon you have to buy the book and then you can download it to your device but on gutenburg its all free and you can download it in different formats like HTML, Epub, kindle, plucker, QiOO mobile, and plain text UTF-8 and put it onto your device.
Useful Links:
http://www.gutenberg.org/wiki/Main_Page
http://www.amazon.co.uk/Kindle-eBooks/b?ie=UTF8&node=341689031
College Blog 