White hat versus black hat: following good practice, good results will ensue
Deceiving search engines at your own peril
Search Engine Optimisation technique is considered white hat if it conforms to the search engines' guidelines and involves no deception. As the search engine guidelines are not written as a series of rules or commandments, this is an important distinction to note. White hat SEO is not just about following guidelines, but is about ensuring that the content a search engine indexes and subsequently ranks is the same content a user will see. White hat advice is generally summed up as creating content for users, not for search engines, and then making that content easily accessible to the spiders, rather than attempting to trick the algorithm from its intended purpose. White hat SEO is in many ways similar to web development that promotes accessibility, although the two are not identical.
Search engines are for ever improving their monitoring of 'bad sites' that serve as link farms, places where people can buy links to increase their own ranking and traffic. This is an increasingly agressive strategy, particularly maintained by Google, where such sites suffer censure and some have recently been forced to close down.
Common black hat SEO techniques used by unethical practioners include:
.Keyword stuffing: Packing long lists of keywords and little else onto your site will get you penalized eventually by search engines.
.Invisible text: This is putting words in white text on a white background in hopes of attracting more search engine spiders. Again, not a good way to attract searchers or search engine crawlers.
.Doorway Pages: These pages are not linked to the menu system of a web site so that the user will never see. It is purely for search engine spiders, and attempts to trick them into indexing the site higher.
Google and other search engines also conduct human reviews where they suspect black hat SEO being practiced and the result will vary from a warning, page rank drop or complete removal from their search engine results.
So a good web site is one that follows good criteria and encourages natural links rather than deceptive links or those created artificially. There is however a gray zone between these, and it is up to the web designer to be up to date on Google policy and what is allowed and what is risky.
I always follow white hat techniques and will never risk the sites I maintain being downgraded. Loss of ranking is always a heavy blow and not worth the risk. Good content, good style will always bring good inlinks, and thus good traffic and steady increase in ranking.