You probably received plenty of results when searching for information about SEO. And I guess you found what you needed after typing ‘free online marketing tool’ in Google’s search box. Behind this simple page of results is a complex system, carefully build and tested, to make more than 100 billion searches per month possible.
This complex system consists out of 3 different parts.
Part 1 – Crawling and Indexing
Google uses automated crawlers who follow links from page to page. All these pages are sorted out by content and other factors. The crawlers then keep track of it in the index. The index is bigger than 100 million gigabytes full of keywords and places where does keywords can be found.
Be careful – if a website does not have incoming links it is not going to be indexed!
Part 2 – Algorithms
Algorithms continue the path by writing programs and formulas to deliver the most relevant results. Algorithms start working right after you type in some words in the search box. They look for clues to understand what you mean. A couple of these clues are spelling, autocomplete, search methods, synonyms. Based on these clues they pick out the best documents from the index.
The last step of the algorithm is to rank the results. This ranking is based on over 200 factors. Some important ones are: does the page have many incoming links, is the document recently posted and is it a safe search?
The final results ends up in a variety of forms visible for the searcher. The best-known form is a snippet, which looks as follows.
Nowadays a snippet can be updated into a ‘rich snippet’. As you can see in the example, authors and images are added.
Part 3 – Fighting spam
To keep the results relevant Google fights against spam 24 hours a day.
Do you want to know how your website becomes the number one result in Google?