As a computer science student at the Univserity of Minnesota, and the TA of a tech-based entrepreneurship class, I am often asked what search engine optimization means, and how you can use techniques to improve the visibility of your website within Google's search results. Well, to quote wikipedia...
"Search engine optimization (SEO) is the process of improving the volume or quality of traffic to a web site from search engines via "natural" or un-paid ("organic" or "algorithmic") search results (SEM), which deals with paid inclusion." as opposed to search engine marketing
There are many to improve your websites visibility within Google, and I will discuss a few of them below:
Google is constantly crawling the web, searching in every nook and cranny to find new content and websites to add to its search engine. The way that Google decides if your site is the "authoritative" source for any particular keywords, it makes note of the display text that is used in combination with your URL in HTML link code. The more links you have, the better. If www.example.com wants to be the authoritative source for Zompire Dracularius, they will use the following link:
<a href="www.example.com">Zompire Dracularius</a>
Google also has a page rank feature, which specifies which websites they think should have the largest vote in authority on the web. A link from a site with a high page rank will give your site better search results than a site with a low page rank.
Having relevant, authoritative content, will improve your search results as well. If users will enjoy your content, they will link to you. If Google notices that you have relevant content that is constantly being changed and updated, then they will favor your site more than one that is stagnant, or does not contain much information.
Certain domain name extensions, and domain name formats can help your google juice. The domain name extensions .org and .edu work better than .com which works better than .biz and .info.
Using a dash in your domain name to separate keywords will also improve your google juice. ie. www.zompire-dracularius.com will do better than www.zompiredracularius.com.
A site map is a code map of your website that tells Google what pages you own. If you make life easier for google, by adding a site map and thus telling their spiders which pages are most important on your site, they will favor you in their search results.
A combination of all three of these tactics, plus others that I did not list, will give your site better search results.