Hypertext is different from text. Hypertext is within the network environment, where hyper links can be embedded within the text. Links allow the author to provide a richer background for the text itself not just limited within the physical text, but linking to the external sources.
The property of hyper link enables hypertext to be different form physical text. For instance, the text in a book potentially lead you to the next page, guiding you to read from page to page in a order. Hypertext is different from this because it gives you power to jump from page to page, in random order and provide you richer context that make the text more comprehensive.
It’s like an encyclopedia, making the text connect to the world rather than only the author. Text is something the author control on you and hypertext is something that empower you to choose what you want.