Some people seem to believe that on the Web, the ends justify the means. There are lots of ways webmasters can try to trick search engines into listing their Web pages high in SERPs, though such a victory doesn't usually last very long.
One of these methods is called keyword stuffing, which skews search engine results by overusing keywords on the page. Usually webmasters will put repeated keywords toward the bottom of the page where most visitors won't see them. They can also use invisible text, text with a color matching the page's background. Since search engine spiders read content through the page's HTML code, they detect text even if people can't see it. Some search engine spiders can identify and ignore text that matches the page's background color.
Webmasters might include irrelevant keywords to trick search engines. The webmasters look to see which search terms are the most popular and then use those words on their Web pages. While search engines might index the page under more keywords, people who follow the SERP links often leave the site once they realize it has little or nothing to do with their search terms.
A webmaster might create Web pages that redirect visitors to another page. The webmaster creates a simple page that includes certain keywords to get listed on a SERP. The page also includes a program that redirects visitors to a different page that often has nothing to do with the original search term. With several pages that each focus on a current hot topic, the webmaster can get a lot of traffic to a particular Web site.
Page stuffing also cheats people out of a fair search engine experience. Webmasters first create a Web page that appears high up on a SERP. Then, the webmaster duplicates the page in the hopes that both pages will make the top results. The webmaster does this repeatedly with the intent to push other results off the top of the SERP and eliminate the competition. Most search engine spiders are able to compare pages against each other and determine if two different pages have the same content.
Selling and farming links are popular black hat SEO techniques. Because many search engines look at links to determine a Web page's relevancy, some webmasters buy links from other sites to boost a page's rank. A link farm is a collection of Web pages that all interlink with one another in order to increase each page's rank. Small link farms seem pretty harmless, but some link farms include hundreds of Web sites, each with a Web page dedicated just to listing links to every other site in the farm. When search engines detect a link selling scheme or link farm, they flag every site involved. Sometimes the search engine will simply demote every page's rank. In other cases, it might ban all the sites from its indexes.
Cheating the system might result in a temporary increase in visitors, but since people normally don't like to be fooled, the benefits are questionable at best. Who wants to return to a site that isn't what it claims to be? Plus, most search engines penalize Web pages that use black hat techniques, which means the webmaster trades a short success for a long-term failure.
In the next section, we'll look at some factors that make SEO more difficult.