The difference between radio and television is simple to express, but its implications are far from trivial. The difference is moving images . Many web designers treat the fluidity of web pages as a flaw. PDF is often touted as the cure for this problem. It is that the designer loses control over their design.
Readers can resize their pages, can choose their own font sizes, in short readers have control.
It's easy to see why designers can consider this, along with the platform differences of different operating systems, browsers and system setups as problems to be solved. Designers in the world of paper based publishing are used to control. A whole industry has evolved to ensure that what the designer wants is what the reader gets. Let's call this facility for readers to be able to adapt web based content for themselves adaptability . My heretical viewpoint is that adaptability isn't a problem, it is a particular strength of the web.