Our research is concerned with the visual representations found in textbooks used for the teaching of the Internet in Greek secondary schools. Visualization, as both the product and the process of creation, interpretation and reflection upon pictures and images, is considered here to be very important, as it is the only way students gain insight into the nature and function of the Internet, its size, complexity and invisibility. Initially, we attempted to analyze and reflect upon school textbooks' visual interpretations of the Internet. A scheme of categories of visual representations has been identified and reveals the characteristics of the textbooks' representations as well as their limitations. Sketch-comics and computer snap-shots are the more popular types of Vrep, although a considerable number of them cannot be characterized as accurate and few of them have an explanatory or complementary function in terms of the content presented in the text. We have also explored the impact on students' readings of two visual representations in one of the textbooks, used without any caption or textual information. The phenomenological aspects of the VRep seem to attract students' attention and create obstacles in conceptualizing the main idea conveyed in both representations, but when the field of ICT is implied and not clearly portrayed in the VRep, students face serious