It's the process of optimising a website so it is better received by search engines. Why optimise a website from the point of view of the search engines? Afterall a website is a resource for humans not search engines, right?

When you consider that almost all web traffic is driven by the major commercial search engines, in particlar Google, Yahoo and MSN, it stands to reason that if your site can not be found by the search engines then it will not be found by people via search. By optimising your website around the potential searches your target consumer market are likely to make you can use search engines to drive large volumes of targetted traffic to your website. Know that's an opportunity every business should be capitalising on.

Is your website working for you?