Web site optimization is the practice of making your site search-friendly both to search engines and searchers. There are five common mistakes that people tend to make when beginning to optimize their sites for search engines.
A lack of targeted keywords and phrases can make or break your site. When a searcher goes to a search engine or directory and types in a keyword or keyword phrase that you would like to be found for - but you don't have these particular keywords and phrases on your site - then that searcher will most likely not be able to find you.
Site content is the absolute number one draw for both search engine spiders and search engine/directory users. If your content is badly written, is never updated, or is not relevant to what you want to be found for, than your site is neither search engine friendly or user-friendly. In addition, your content absolutely must have targeted keywords and phrases (see mistake number 1). Well-written content is what search engine spiders feed on, and content is the key to high rankings.
Black Hat web site optimization includes techniques that are unethical and frowned upon by search engine spiders. These techniques include keyword stuffing, doorway pages, invisible text, and more. These practices actually do raise your site ranking. However, search engine spiders have become very aware of Black Hat seo techniques and can spot them pretty easily (and ban your site). Don't go for the quick fix; learn how to optimize your site for the long haul.
Meta tags include title tags, keyword tags, and description tags. While not the absolute most important component in Web site optimization (that spot is reserved for keywords and content), they do have an important part to play. Make sure to include all these tags in every page of your site, and target them for each individual page.
Ineffective site design includes lack of clear navigation, poorly designed frames, and large,load-intensive graphics. Search engine spiders can actually be blocked from crawling sites that are not well-designed, so it's a major part of Web site optimization; plus, if users can't find what they want on your site quickly, they'll find another site.