A paper book is more than simple content. We can define paper books by: object which holds in both hands, turning pages, its paper quality, its smell. A paper book is also structured content, divided into chapters, page numbers, which is read linearly.

Throughout the ages, the form of books has evolved. The arrival of new information technologies has changed our habits of reading: we devour, savour, peck stories and latest news. Any time of day, we want to access to numeric content whether at home, at work or on the road. The development of the Internet has largely contributed, through dematerialization which has occurred in many areas, including the media. If this mutation was triggered quickly enough for music and movies, it was slower regarding the book.

Nowadays, the market offers various products grouped under the designation of ebook, sometimes with very different appearances. What is it exactly an ebook? A new variant of paper book, it meets the needs of dematerialization: easier storage, transportation and access, etc. At its beginning, ebook was built from HTML, XML and CSS files, grouped together in a compressed folder, reforming the structure of the book. This technique is proposed by the IDPF with the open and standardized file format called EPUB. Thanks to adopted technologies, it benefits from their technological advances and can offer: adaptability of content to different types of screens, customizing the rendering or integration of basic multimedia content. This format is widely used by the book industry to dematerialize literary catalogues. The market offer is mainly homothetic and subjected to DRM.

Overtime, digital book industry has become more complex with a market that wants to offer more than just simple books. From now on, producers want to offer more enrichment, interactivity and even more (external) content. This trend is strongly influenced by the development of mobile devices such as tablets, e-readers and smartphones, allowing more and more features, far beyond the traditional reading. In response, ebook will decline under various digital forms, whether in proprietary formats or in-house solutions.

This market is now fragmented and the digital book world is most difficult to define, both for consumers and producers: everyone offers its catalogue of ebooks, its sales channels with its own format / solution, requiring a compatible player/reader.

Today, ebook is always subject to change, both in its form and its content. Open-plan, overflowing content, what type of ebook for what type of content? New considerations and challenges for production, layout, narration, enrichment, interactivity and compatibility.

Ebook, is it only a label that is placed on a virtual object, with still poorly defined characteristics?