The way Google previously worked was by crawling the web for a period of time and then pushing those updates out every so often. For example, they would crawl for 30 days, take down an old data center and then push out a new datacenter in it’s place. This is what caused the “Google Dance” that would cause people to become frantic in the forums because their rankings would be jumping around all over the place.
Here’s a great video explaining that and a lot of what the rest of my post is actually about. There is a ton of great info from Matt Cutts here, so watch it if you have time:
There are a few key points that I’ve gathered from the video above.
First is that Google’s “Caffeine” update was created to index the web much more rapidly. Instead of waiting 30 days to push out an update, Caffeine will find a page/document and put it immediately through indexing. This means that now lots of documents can be crawled and pushed out onto the web within a matter of minutes.
Matt Cutts also mentioned a few ranking factors that Google specifically looks for. They are already commonly known, but worth mentioning again.
- Languages of content
- Languages of linking content
- Incoming links
- Anchor Text
- Page Rank
So basically what Google does is it after a page enters the indexing phase, it figures out what’s attached to that document – what links are going to it, the anchor text of those links and page rank coming in. It will find all of the signals from various sources and attach it to the page, which will then determine where to rank it.
By the way, I’d like to mention that when Matt Cutts mentions Page Rank, he’s not talking about toolbar PR, but instead the internal Page Rank known only by Google.
The factors mentioned above are only six of the 200+ ranking factors that Google uses. I would suggest you check out SEOMoz’s Search Engine Ranking Factors 2009 for much more thorough list of factors and their importance as voted on by top SEOs in the industry.
Also, note that with the Google “Mayday” update that just recently went into effect, keep in mind that it’s not just about ranking factors anymore. Pages that are low-quality, have small amounts of content or are seen as “thin” by Google are being weeded out of the index. I’ve already seen several instances of this happening with lots of sites, mainly in e-commerce or affiliate marketing. It’s common for e-commerce and affiliate sites to be light on content or containing only short reviews or common product descriptions, so consider adding some valuable content now before you take a hit.
After you’ve added value to your sites, then you can start to think about ranking factors.