In an environment where being better in the rankings among your peers is a must, not all methods commonly employed to achieve this superiority could be considered ethical. There are certain SEO tactics that one should not use, because they can put you on bad terms with the very search engines you are trying to use to your advantage.
For example if you wanted to increase your pagerank, the ethical thing to do would be to look for sites of similar type content and try to get some backlinks. You may even post articles to a directory, or try to get the homepage in several directories. All these things are perfectly normal and are beneficial to the growth of a website. However there are ways in which you can do these things that make them suddenly seem shady.
Keyword cramming would be one fine example of these tactics in use, which basically consists of cramming an inappropriate amount of keywords into a small space. The hope is that this cluster of tightly packed words will catch users as they type parts of these phrases into a search engine. Unfortunately this type of SEO will get you put down by the big engines, as they do not take too kindly to keyword crammers and link farmers.
Another common yet unethical method of SEO is the briefly aforementioned link farm. Backlinks are an integral part of good SEO, because of their effect on the pagerank of a site. Link farms take this notion to the unethical extreme and are sites that consist entirely of backlinks. These backlink pits are a dime a dozen across the internet and do not serve to help anyone. In fact they are likely to get your site penalized if you do not avoid them, and you may end up on sort of a search engine “blacklist” if you are caught.
There are enough good SEO techniques that someone should never have to resort to the shadier ones, but it still manages to happen on a regular basis. Good techniques that will boost your site and not hurt your standing with the engines would be having good content, using appropriate meta tags, repeating relevant keywords within the title and body of the content, and getting legitimate backlinks. If you manage to do all these things and avoid the spammy link farms you should be well on your way to a highly optimized website.
If there is one thing in particular to focus on out of all the other SEO principles however, standing out above the rest is content. Content is what keeps the visitors coming back, content is what your site actually is, and what it is about. Having unique content that your visitors only get at your site is a huge advantage online, and should be a goal for any business or personal website. Original content will insure that your site continues to keep it’s visitor base coming back for more, and this is what separates failing sites from thriving sites.

Internet marketing is a highly lucrative activity to get into. At the same time, many people who attempt this tend to fail. The reason for this is that so many people expect it to be as simple as write content and then you will make money. There is a lot more that goes into it than that. There are quite a few different methods and avenues that you must look at in order to maximize your success at internet marketing.