Blurbs: How to Write Them for Web Pages
http://jerz.setonhill.edu/writing/e-text/blurbs.htm

Jerz, Dennis G.
Seton Hill University
2001

Abstract:

On the web, a blurb is a line or short paragraph (20-50 words) that evaluates (or at least summarizes) what the reader will find at the other end of a link. A good blurb should inform, not tease. Usability testing will help you determine the best way to lay out your blurbs, but this document will help you write the content.