This is the very briefest of introductions to the World Wide Web. For more about the Web see the links below. As you see on this page, text can be arranged into sections with headings, paragraphs, and lists. Either as information themselves, or to beautify the page. In that part there may be references to images, which are then read and merged into the text.
Images can be very much bigger than the text part of a page.
Links This is where the magic is. One Web page may refer to other Web pages, linking to information elsewhere. This Web page contains quite a few links. Links may also be represented by an image or even part of an image. To follow a link you just point at it with the mouse, and click.