The Art of SEO, 2nd Edition

Making Your Site Accessible to Search Engines

The first step in the SEO design process is to ensure that your site can be found and crawled by the search engines. This is not as simple as it sounds, as there are many popular web design and implementation constructs that the crawlers may not understand.

Indexable Content

To rank well in the search engines, your site’s content—that is, the material available to visitors of your site—should be in HTML text form. For example, while the search engines do crawl images and Flash files, these are content types that are difficult for search engines to analyze, and therefore they do not help them determine the topical relevance of your pages. With Flash, for example, while specific .swf files (the most common file extension for Flash) can be crawled and indexed—and are often found when the user searches for specific words or phrases that appear in their filenames and indicates that he is searching only for .swf files—it is rare that a generic query returns a Flash file or a website generated entirely in Flash as a highly relevant result, due to the lack of “readable” content. This is not to say that websites developed using Flash are inherently irrelevant, or that it is impossible to successfully optimize a website that uses Flash for search; however, in our experience the preference is almost always given to HTML-based files.

The search engines also face challenges with “identifying” images from a relevance perspective, as there are minimal ...