Now You got an idea of the basics of SEO.
Search engine Perform three functions:
· Crawling – Crawling is the process in which search engine send team of robots(crawlers or spider) to fetch all the web pages or to find new content. Content could be a webpage, an image, a video, a PDF, etc.
Googlebot starts fetching a web pages, and follow the links on those webpages and find new URLs. In this way robots find a new content and add it to index called Caffeine.
· Indexing – When robots find a new content and add it to index called Caffeine. A process of creating massive database for all the fetched web pages from where it can later be retrieved.
In our old index we had several layers, Some layers are up[dated faster than others, main layer would update every couple of weeks. To refresh a layer of the old index, we would analyse the entire web, which meant there was a significant delay between when we found a page and made it available to you.
With Caffeine, we analyze the web in small portions and update our search index on a continuous basis, globally.
· Processing – When a search request comes, the search engine processes it, i.e. it compares the search string in the search request with the indexed pages in the database.
· Calculate Relevancy – It is likely that more than one page contains the search string, so the search engine starts calculating the relevancy of each of the pages in its index to the search string.
· Retrieve Results – The last step in search engine activities is retrieving the best matched results. Basically, it is nothing more than simply displaying them in the browser.
Search engines such as Google update their algorithm so many times per month. Whenever we see changes in rankings it is due to an updating in algorithms.
Although the basic principle of all search engines is same, as the minor differences between their relevancy algorithms lead to major changes in results relevancy.