Search Engine Optimization (SEO) is a difficult area of expertise. And Google in the past hasn't always be that helpful to webmasters as to give them insights in how to get it done properly. But now, the people from the Google Webmaster Help group have put together a SEO Starter Guide.
In a 22-page long document, the basics of SEO (according to Google) are laid out, ranging from the use of page title and description tags (you don't use the 'keywords' tag anymore now, do you?) over the optimal structure of URLs, site navigation, the use of the robots.txt file and good HTML up to website promotion and handy webmaster tools.
As the title says, it's a 'starter guide'. So don't expect an advanced manual on SEO. But to get a first grip on the matter, it certainly is a good starting point.
> download the document