Matt Cutts, head of the Google’s webspam team, details in a YouTube video how the search engine giant thoroughly scours the web on a daily basis to provide the most up-to-date results to users.
Google launched this site ‘How Search Works’ a little less than a year ago, although Google crawls the web on daily basis, that wasn’t always the case. “We used to crawl for 30 days… and then index for about a week and push that data out — and that would take about a week,” Cutts said. “Sometimes you would hit a data center with new data and sometimes you would hit a data center with old data.”
Page rank is the key indicating factor as to how likely you are to see a link, the more page rank you have- that is, the more people link to you and the more reputable those people are-the more likely it is that we will discover your page relatively early in the crawl,” Cutts said.
For “Site & Page Quality,” Google says, “Uses a set of signals to determine how trustworthy, reputable, or authoritative a source is. Google then runs through the various types of spam: cloaking and/or sneaky redirects, hacked site, hidden text and/or keyword stuffing, parked domains, pure spam, spammy free hosts and dynamic DNS providers, thin content with little or no added value, unnatural links from a site, unnatural links to a site, and user-generated spam.
In the recent YouTube webmaster help video featuring Matt Cutts talks about something “You might have not noticed” about the company’s ‘How Search Works site’
One thing he mentions is where it says how many searches Google has handled in the time that you’ve spent on the page. He then talks about different elements of the site for about ten minutes, so if you haven’t spent much time perusing it, you may want to listen to what he has to say. You might find something that captures your interest.