What is it?
Search engine optimisation, or SEO, refers to the practice of improving your website's ranking with various search engines in association with specific key search terms or phrases. For example, a website that sells gardening supplies would probably want to be as close to the top of the results list as possible for search terms like "gardening", "plants", "gardens" and the like. The goal of SEO is to increase traffic to your website from search engines.
How does it work?
Search engines use automated programs that surf the web methodically and store information about all of the websites that they visit. The information that they store is then analyzed to decide what ranking each website will receive in association to which keywords. Generally speaking, these programs use three techniques to discern a web page's ranking in the results for specific terms. These techniques are the evaluation of keywords, inbound links, and the URL or web address.
Keywords
Search engines evaluate meta data and what's called keyword saturation to decide what a web page is about and where it ranks for its keywords. Meta data is defined using the HTML meta tag in conjunction with the attributes name ="keywords" and name="description". Here you write out a short description of your web page as well as the keywords you would like associated with it. This data won't be shown to your users but is considered by search engine crawlers, that is, those automated search engine programs mentioned earlier. You can learn more about using meta tags by doing a simple google search for "HTML meta tag". While defining meta tags for your content is not a bad idea, search engines care a whole lot more about the actual, readable content of your website than its meta data.
The readable content of your website is evaluated by the amount of times specific keywords occur within the text. Search engines place more value on words within title, heading and strong tags than regular text, which means that you'll want to make sure these parts of your website are as relevant as possible. Different SEO experts will tell you different things regarding exact, optimal keyword densities, but generally the number will fall between two and seven percent. This means that approximately two to seven percent of the words in your text should be keywords that you imagine people will search for when seeking your content.
Don't go overboard when improving the relevance of your titles and headings or the saturation of keywords in your text. More and more search engines are removing content from their databases altogether if it appears to be taking unfair advantage of keyword optimization. The rule of thumb is to keep your text clear, natural and readable to your users; if text appears to be composed more for the consumption of crawlers than people, your website's ranking could be penalized.
Inbound Links
An inbound link is a link to one of the pages in your website. Search engines evaluate the number of inbound links and the labels of those links to better understand your content offerings. If, for instance, there are several links leading to pages within your website with labels like "Dog food" and "Pet food", your ranking for those search terms will improve. Evaluating these links is a pretty big part of the overall ranking process, so it's important that you do what you can to improve the amount and accuracy of your incoming links.
While strategies like business to business networking and social media advertising, (promoting your products with applications like Facebook or Twitter), can have a positive impact on your inbound links, the best strategy is to provide relevant content, and products and services that keep your users satisfied and coming back. As your rapport with your user base grows, you'll find that more and more websites link to your content or products as being a trusted source in your industry. It's important to note that much like the case with keywords, search engines seek out and penalize unfair or unnatural linking such as spam or supporting websites set up solely for the purpose of linking to your main website.
Readable URLs
A readable URL is a web address that is human readable and semantically relevant. For example, a human readable URL for a newspaper article about decreasing wages might look something like this: http://newswebsite.com/10-11-2009/economy/decreasing-wages-in-example-city. A non readable, or unfriendly URL for the same article might look something like this: http://newswebsite.com?issue=yes&date=1255305866&cat=econ&id=34. It's pretty easy to tell the difference. With a readable URL it's easy for both your users and search engines to make some assumptions about the web page's content; in our example above, it would be safe to assume just from the URL that the article concerns the economy, is current, and specifically concerns "decreasing wages" and "example city". This relevance can greatly improve your search engine ranking and the usability of your website. So how do you create clean URLs? If you're using a content management system or CMS to drive your website, it may be a configuration option that you can choose, otherwise you'll need to edit your .htaccess file as well as know a bit about programming. You can learn more about the latter with a simple google search for "clean urls with htaccess".
