These documents can contain text, images, sound, and so forth. All Web documents use a standard format called HTML, HyperText Markup Language. Hypertext lets you jump from one document to another using links.
Links are places in documents that contain information about related documents.
These links are usually displayed as colored words on your screen. You can click on these links to be connected to the related documents. Here is an example of how this might work. Perhaps you are reading an article about the Museum of Paleontology at the University of California, Berkeley. You might notice the link in that document referring you to other on-line natural history collections.