Introduction
Some webmasters claim that more than a half the total traffic on their sites comes from search engines. This share, of course, will depend on the content of your site and the sort of audience you're after, but in any case the importance of this free and efficient web advertisement tool cannot be denied.
Admittedly, traffic generated by search engines always contains a lot of "junk"---that is, useless visits from people who were mislead to your site by "keywords divination" in search of something completely different. However, those surfers who ended up finding what they were looking for are a very valuable category---maybe the most valuable of all your audience.
They might have never learned about your site from any other source, and having found it themselves, without any advertising or endorsement, they're more likely to be satisfied by the discovery. In fact, search engines are the closest possible approximation to the ideal of free and independent dissemination of information: You search for what you need, and you get what you searched for, with no marketing or political bias.
Of course this ideal doesn't come cheap. You'll have to learn some techniques to lure and welcome at your site, first, automatic spiders indexing your page for search engines, and second, search engine users who might be interested in your content (these tasks are a bit different, although interrelated).
This chapter contains two major sections. In the first section, you'll get acquainted with how search engines work and what are the main features of the major engines now in operation. In the second section, I'll apply this knowledge to outline a set of specific recommendations for an efficient search-friendly HTML design.
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