Daring Fireball: Kottke on the Art and Power of Hypertextual Writing
Hypertext links are an information-density multiplier.
The way I’ve long thought about it is that traditional writing — like for print — feels two-dimensional. Writing for the web adds a third dimension. It’s not an equal dimension, though. It doesn’t turn writing from a flat plane into a full three-dimensional cube. It’s still primarily about the same two dimensions as old-fashioned writing. What hypertext links provide is an extra layer of depth. Just the fact that the links are there — even if you, the reader, don’t follow them — makes a sentence read slightly differently. It adds meaning in a way that is unique to the web as a medium for prose.