The contribution presents an overview and analysis of representative researches results concerning the influence of the Internet on mathematics teaching and learning. The researches have been divided into categories according to their research focus.
The second part focuses on free web resources. Website functions are being discussed in comparison to textbooks from the learning process point of view.
Based on the investigation of a range of websites, the benefits and risks associated with web sites use in mathematics instruction are stated. These include an analysis of some mathematical and didactical errors in these resources.