What is SERP? - How Search Engines Determine SERP

To understand how search engines decide which websites to display in their SERP and where, we must first understand how a search engine views and indexes a webpage.

Search engines have automated robots (often called spiders) which constantly “crawl” the World Wide Web and gather, as well as store information about the billions of webpages they crawl. When someone performs a search the search engine reaches into its storage of billions of pieces of information and, based on complex algorithms, returns what it deems to be the most relevant and important results for that search. The results calculated to be most relevant and most important for that search will be returned at the highest SERP rankings.

What is considered relevant and important is based on hundreds of factors, some of which remain unknown. However, those factors which are known can be used to increase a site’s relevancy and importance in the eyes of the search engine – this is search engine optimization.