What is a textbook and what is the difference between the classic, printed textbook and hypertext textbook on the web? Experts offer different definitions of what a textbook is. The most often used definition is the one which links the textbook to curriculum.

As the basic teaching tool, in time textbook acquired a recognizable internal division.

The structure of a textbook is characterized by division into chapters describing units within the given subject. Such structure is adjusted to the printed materials and it is no disadvantage if one chapter in such format has 20, 30 or 50 pages. In a hypertext textbook it would, however, be ideal if one unit of knowledge could be displayed on just one screen. It is, of course, not always possible, despite the fact that the use of links enables the author to create a hypertext material which presents the subject of study in a more compact manner.

The structure of a hypertext textbook will be somewhat different from the classic printed textbook, since the author will have to take into consideration the characteristics of the medium. Such textbook structure will in principle consist of a bigger number of smaller units. 

There are many university textbooks on the web that are nothing more but an electronic version of a printed book. That is the natural flow of things. The authors wanted to make their works available over the web, and the only materials which they had at their disposal were classical printed textbooks. In time the share of educational materials originally written in a hypertext format will grow.

Why put the electronic version of the printed textbook on the web? There is no doubt that this way the textbook will be available to all who are interested. This approach is good for the students, the other users of the book, as well as the author/s, since it gives the book an opportunity for affirmation in a wider range than through classic book sales.  

The drawback of this method is that it, in most cases, leaves the author (and/or publisher) without the copyright, which can be easily controlled through book sales. One of the possible and more effective control methods of control of the use and compensation for reading the book on the web is through the regulation of access to the full version of the book.

Textbooks which were originally written as hypertext materials cannot be printed as a book in its integral format. The basic technical characteristic of hypertext textbooks is that links binding different sections of the material are built into their structure. Every user of a hypertext material can interpret it in their individual way.

Hypertext textbooks can include multimedia elements, which are impossible to include into the classical printed textbook.