**2.1 E-learning models**

Currently, there are a number of E-learning models (Butz, 2006) developed and used worldwide in distance education. Each university, or other institution provides such programs by adopting an appropriate model - a model that it deems to be the most effective for its intended type of training.

The first model is the *self-directed E-learning*. This model is the simplest with respect to the number of functionalities, and is aimed at experienced learners in the process of continuous professional development, who wish to deepen specific topics. The information content consists of web pages, multimedia presentations, audio-video presentations and other materials. The content is made available to users via a hosting Web server.

The second model is called *facilitated E-learning*. This system combines the self-directed elearning architecture model with a range of communication facilities, such as the email or the discussion forums. Documents are often transferred through the forum, where all users have access.

The third model is the *advanced E-learning,* which uses advanced Web technologies for the management of the entire educational process. Such a model uses audio-video real time transmission techniques via video telephony or video conferencing applications, chat or smart boards. These facilities are added on top of the previous model. Also, the educational process follows a timetable that all the students are required to meet. Such a model is built on the LMS system (Learning Management System). The information content is covered gradually, allowing the student to deepen all aspects of a topic.
