Whereas traditional writing on paper tends to be linear you start at the beginning, and go through to the end it needn't be; it can, in fact, be designed to let you jump around between related ideas. This is possible on paper the "See Also" section of an encylcopedia entry is the same idea, as are the "choose-your-own-adventure" books ("If you want to open the door, turn to page 73") but it's cumbersome.
But with computer technology, it's easy to direct readers to related ideas. This computer-based glossary is hypertextual: I can refer you to terms like Alexandrine and Postmodern, and you can go directly there and once there, you can follow links elsewhere. Text turns into a web of connections, and the reader chooses which connections to follow.
The World Wide Web is a huge collection of hypertext documents, where each page on the Web can refer to any other page on the Web.
Note: This guide is still in the early stages of development.
Three question marks mean I have to write more on the subject. Bear with me.