We selected these sites for our Showcase because they illustrate features of good web writing. It's harder to read a computer screen than a printed page. The screen contains less text than the printed page. Reading online is slower and quickly causes eyestrain.
Online readers are impatient.
They want to be able to find what they need quickly. Online readers aren't linear. They move quickly through the document in whatever order suits them as they try to grab the information they need. Online readers are skeptical. They want online writing to assert its credibility right away.