Google's stated mission is to organize the world's information and make it universally accessible and useful. Without Google and other search engines, trying to find anything on the internet would be nearly impossible.
Step One: Gather the Information
Before you can find the information you are looking for, Google first has to acquire that information and store it on their servers. To do this, Google sends out bits of code (called spiders) to scour the web to discover new and revised content. These spiders rely on a web page's links to move from one web page to another to compile the information for the Google index. Naturally, content is added and changed constantly, therefore Google's spiders are at work constantly.
Step Two: Index the Results
When you use Google or another search engine, you aren't really searching the internet, you are searching their index of the internet.
Once the Googlebot crawls the web page, it indexes the words on that page plus other bits of information that the page contains such as the title tag, the alt tags for image, etc. and stores that information on one of the worlds most extensive server networks.
Step Three: Rank the Results
Once all of this information is compiled on the Google servers, the Google rankings algorithm takes over in an attempt to
understand exactly what you mean and give you back exactly what you want. To do this, Google tries to emulate and anticipate how humans interact with the Internet. According to researchers, over 200 variables are taken into account in order to provide the searcher with the infomation deemed to be most relevant. Of course, to protect their business interests and to keep the search results valid, Google doesn't make all of those rankings criteria known. However, there are core components that they have shared:
PageRank is the measure of the importance of a page based on the incoming links from other pages. In simple terms, each link to a page on your site from another site adds to your site's PageRank. But not all links are equal. To be weighted more heavily, a link must be related.
Content Relevance and Quality
Content is king. Google is looking for well written content that has the words from the search query on the web page, with greater weight given to the occurences of the search query in important places on the page such as the page title, the page heading, etc. However, the Google algorithm is sophisticated enough to know if a page is trying to game the system and will try to filter out theses results.
Other factors related to content relevance and quality include:
- A mobile-friendly site is a must
- A larger site with more pages (and thus more content) is generally better
- Brand-new sites and old, stale sites may be demoted in the rankings
- Ad heavy sites may rank lower
- Repetition of keywords in the site content may get a page filterd from the results
Google takes into account the context of your search to provide results that are going to be relevant to you. Knowledge of your location, your web history and even the device you are using to conduct the search are taken into account when providing the search results. For example, a search for
ice cream shops is very likely to produce a list of shops within your geographic region. You aren't likely to see results from Brazil or England (unless of course you live in either of those two countries).
Google is the premier search engine in existence today. They do a fantastic job in providing users with the results relevant to the search conducted. They are constantly revising their methods to improve the performance of the search experience.
They have added additional services to assist in making search better, and they have also added services that appear to have no relevance to search activity at all.