Also, consider technical factors. If a site has a slow connection, it might time-out for the crawler. Very complex pages, too, may time out before the crawler can harvest the text. If you have a hierarchy of directories at your site, put the most important information high, not deep. Some search engines will presume that the higher you placed the information, the more important it is. And crawlers may not venture deeper than three or four or five directory levels. Above all remember the obvious - full-text search engines such index text. You may well be tempted to use fancy and expensive design techniques that either block search engine crawlers or leave your pages with very little plain text that can be indexed. Don’t fall prey to that temptation.