Web Style Guide

Web Style Guide: Basic Design Principles for Creating Web Sites by P.J. Lynch and Sarah Horton, Yale University Press 2002

Buy online:
    Amazon.com (usually cheapest cover price)
    Amazon.co.uk (P&P cheaper & quicker in EU) 

Web Style Guide: Basic Design Principles for Creating Web Sites is a wonderful guide to online site design.

The book begins with a discussion of  defining the objectives and users of your Web site, and measures of progress. Traditional print concepts are used to illustrate how to make your site welcoming and efficient. The sections on typography and editorial style set this manual apart from many Web style guides with attention to the fine details that separate the good sites from the great.

Multimedia elements and cascading style sheets (CSS) are covered within the context of building a great site. 

You can read a topic and then go online to see the concepts in action. Web Style Guide delivers some of the best coverage of site design you'll find anywhere.