And it's important. Can't remember the source now, but for years I've been quoting a couple of pretty stark statistics:
- Around a third of people don't get below the fold on the first page of search engine results, so only see about 4 items
- Around two thirds of people don't go beyond the first page of results. They'd prefer to refine their search terms than move onto page 2.
So understanding how and why search engines rank web pages the way they do is pretty fundamental.
And this graphic represents what you need to know beautifully.
The periodic table of search engine optimisation (SEO) ranking factors - searchengineland.com