Matt Cutts did a video about search snippets during his recent visit to the Google Kirkland office. In it Matt takes a detailed look at how Google constructs a search snippet. Matt uses the example of a search on "Starbucks", which results in the following search result:
Here is a summary of the observations by Matt, with a few incremental comments sprinkled in by me:
The title of the snippet comes from the title of your page. In this case, it's "Starbucks Homepage" and the SEO advice that Matt provides is that you might want to have this say "Starbucks Coffee" instead. Now in the case of Starbucks, they already rank #1 for the term "Starbucks Coffee" any way, so the advice may not be important to them. For most web sites, however, Matt's advice is critical.
To paraphrase: Get the keywords that are most relevant to your web page in the title of the page. Do this in a way that does not baffle the user, as this will lower your click throughs to your site. Do this for all the pages on your site.
Next up is the description. This can come from multiple places. First of all, if Google can't currently crawl your page for some reason (e.g. you server is down when the Googlebot comes visiting) Google can't construct the description snippet from your page. This is the one scenario where you may see Google using the Open Directory Project (aka "DMOZ") description for your site (if such a description exists).
Next, Google looks to see if they can find text within the user visible part of the page itself that matches up with the query. For example, if the search was for a specific name, and that name shows up at the bottom of the page in the text, the description snippet will likely get pulled from there, even though it is way down on the page. Google does this to help searchers more rapidly determine the relevance of the returned result to the query.
If Google is not satisfied that what they find in the user visible text of the page matcehs up with the query they are then likely to return the contents of the met description tag. This is why this tag is so important. While it does not influence rankings in any search engine I know about, it is a powerful opportunity to entice the user to click on your listing instead of someone else's.
The other thing that Matt observes about the title and the description in the result, is that keywords from your search query will be bolded. For that matter, if the keyword appears in your URL, that will also be bolded, but we'll cover the URL separately in a moment.
Matt notes that Google does know about stemming and synonyms, so if your search includes the word "car" in it, that it will understand that this is the same as "automobile" and potentially the same as "auto". However, in this example, automobile and auto will not be highlighted in the search results, only car will.
Over to the right of the description you will see a link to get a stock quote for Starbucks. This is because Google knows that Starbucks is a public company, and many of their users who search on Starbucks may be looking for a stock quote. Similarly, if their is an address on the page, Google may show a link to a Google Map for that location.
Below the description you will see a line that has the URL in it. This is simply the URL of the page for this search result. As mentioned above, a portion of this may be bolded if the a word from the search query shows up in it.
Just to the right of the URL you will see a page size, 12K in our example. Sometimes you will also see a time stamp for when it was last crawled. This likely shows up most on those sites where freshness matters.
Further to the right of the URL, you see a link called "Cached". This shows the copy of the page that Google last obtained from your site. At the top of the cached page you will also see information on when Google last retrieved the page from your site. The cashed page is one way for you to see if Google has seen your latest changes. In addition, searchers can click on this is for some reason you site is currently down.
To the right of the Cached link appears "Similar Pages". This is a link that will show you links to other similar sites. In Starbucks case, you get Starbucks Japan, Pizza Hut, Peet's, Quiznos, and other food and beverage chains.
"Note This" is a link that shows up over on if you happen to be logged into Google Notebook (I was not for my screen shot). You can use that link to save a bunch of links if you are actively researching something.
Next up is the site links. Google only does this for some sites. As Matt clarifies in the video, there is no way to pay to get Google to put up sitelinks for your site, it is done completely algorithmically. The sitelinks show other pages within the site that are very popular.
Basically, Google is trying to help the user get to the page they really want much more quickly. If they really wanted to see the About Us page, for example, this presentation will save the user a click.
Lastly, there is the "More results from starbucks.com" link at the bottom of the snippet. Clicking on this will automatically generate a " site:starbucks.com starbucks" query for you, which will basically repeat your orignal query, but limit the search results to those pages on the starbucks.com site.
That provides a pretty complete look at a Google search result snippet. Matt has promised more videos and I will make a point of covering them all in detail as they come out.