While there are many legitimate skills in SEO there are also those that can work but if you get caught using them the results can be disastrous. When search engine optimization became an issue many techniques were employed because at that point the search engines used a much simpler algorithm. As these tricks were used to exploit the simpler algorithms they were also served to make them more advanced. Let's look at a few tricks.

Cloaking and redirects are methods whereby you show one page to the search engine but a different one to the visitor. A redirect merely brings visitors to one page and then sends them to another page by refreshing the page with one on their site. Cloaking involves fooling a search engine's indexer into thinking that it is something else and getting the indexer to send false information back to its boss.

Other techniques involve overloading metatags with keywords or even hiding keywords in plain site on the webpage. A variation on this technique is to shrink the keywords so that are too small to be seen by the naked eye.

Using unrelated keywords is another trick especially when combined with the above mentioned tricks. By using unrelated keywords in this manner you can drive traffic to your site from multiple sources.

Using an overly optimized landing page can also work. This is not the same thing as a legitimate landing page. In this case you use any and all methods to overly optimize a single and use that to lead people to your site. This would involve using all of the above methods for this one page.

The ultimate penalty for using the unscrupulous methods is banishment from the search engines themselves. Be careful when you employ these dark methods for fear of this punishment. Being penalized is one thing but to not even be on a search engine in the first place is your worst case scenario.