Ian Lurie // Oct 25 2007
Note: If you’re a veteran SEO person, this article is probably too basic. Read if you like, but this is meant as an introduction to how search engines ‘think’.
With all the hysteria lately over Google’s pagerank changes, I thought a refresher on basic search principles might be helpful.
Search engines are hierarchical beasts. They see the internet as a series of structures, and while we can’t say exactly what those structures are, there’s a well-known method to the madness. The typical search engine algorithm looks first at the entire internet, then at your site, and then at each page on your site:
You’ve probably heard lots about linking. It’s true, more links are better. That’s because search engines are measuring your relative importance and relevance using links:
The more links you have from relevant sites, the more important you are. Search engines build a humungous pyramid/cube/sphere-shaped amoeba thingy based on all of those links.
Think of them as votes. More important pages have more votes.
Search engines determine relevance based on link text (the text that’s ‘live’, like this) and the overall relevance of the linking page and site to the topic searched. So, if you have links from 500 sites that deal exclusively with the Toyota Prius, then you’ll appear more relevant for that topic.
There’s more to this, too: The text immediately around a link can matter, as can the structure of the page and site. But if you can grasp the basic rule, the rest is easier:
More links from relevant sites = More leverage
Relevant link text = More relevance
Note: SEOMoz.org has a lovely tool that’ll help you analyze the text in links pointing to your site.
The next hierarchy a search engine examines is the structure of your site, and where pages reside within that structure. Pages fewer clicks from the home page are considered more important. Pages further away move down the pyramid:
Once again, link text matters. If one page on your site has 40 inward links from other pages, and the text of that link contains ‘Toyota Prius’, then search engines will judge that page more relevant.
And, once again, there’s more to this rule. Keep the basics in mind:
Closer to your home page = More important = More leverage
More links with relevant link text = More relevance to that phrase
Finally, the search engines look at each page of your site, weighing that page’s relevance, quality and overall importance relative to your site and the internet as a whole. The engines look for a structure within each page:
Title tags are really, really important. Heading tags are, too. But what’s really important is that you assign the right structural markup to each element. Headings should be within a heading element, like this: <H1>. That tells the search engine that it’s looking at a heading, and that it should assign that text extra importance in the hierarchy of the page.
Make sure paragraphs are within paragraph elements, tables are only used to present data, etc.. I won’t try to teach you proper semantic markup here. Digital Web Magazine does it far better in this article.
Page-level structure is about doing what makes sense: The title should describe the page. The headings should describe the paragraphs below them. Each paragraph should discuss an idea. And so on. Stick to that, and you’ll do fine.
How important is semantic markup? My company competes with 53 million other pages for the top ‘internet marketing agency’ spot. We’re number two. Here’s why:
We made our move into the #2 spot when we tweaked our heading and title tags. But we only managed it because the surrounding paragraphs discussed the same topic. And even then, we only succeeded because we used proper semantic code: The search engines know that the bold red text is a heading and therefore describes the copy that comes below it.
(I’ve always wanted to say that in a blog post.)
It’s tempting to go back to your site and manipulate title tags, etc. in an effort to ‘trick’ search engines. And the truth is, some level of tweaking with search engines in mind is a must – chances are all your competitors are doing it, and if you don’t, you won’t keep up.
But the best thing you can do is remember this: Search engines want to figure out what your site is about. If you write great, topical copy and insert it into pages with correct semantic markup, in a site that’s well-structured, then other sites will link to you. And search engines will assign you the relevance you deserve.
Ian Lurie is founder and CEO of Portent Inc., an internet marketing agency that has provided internet marketing, including PPC, SEO, social and analytics services, since 1995. Read More