How Do Search Engines Actually Work?

You are currently viewing How Do Search Engines Actually Work?

We all use search engines. But do you know how these search engines actually work?  They crawl web pages with the help of bots known as spiders. The web crawlers follow Links from page to page, and they always look for new content to add a search index. If you have been wondering how search engines work, this article has got you covered.

Search engines crawl and index hundreds of billions of web pages that are submitted to the internet daily. Every time a search is performed, bots get millions of pages that are made available to them. Though all of them have related and helpful information, search engines figure out the pages to display.

The algorithm for displaying relevant web pages starts way before you type your search query. Let us find out more about how search engines make the best information available to their users. Working of search engines is pretty different compared to how it used to work back in the 1990s.

Behind the displayed results on SERPs, there lies a lot of groundwork. However, search engines are secretive about the mechanisms behind the displayed results; marketers obtain maximum benefits by knowing how search engines work. If you want to secure higher ranks on the search engines, knowing how they work, organizing, and picking results to display will help you optimize the web pages better.

Did you know? “Search engine marketing and search engine optimization are critical for online businesses. You can spend every penny in getting your website built, but it will be good for nothing if nobody is aware that your website exists“.

The Basics of How Search Engine Works

A search engine has multiple mechanisms that are interlinked to each other, and all of them work together to identify different pieces of web content that a user asks for. The content may either be text, images, videos, web pages, etc. Then, depending on the search query typed in the search bar, the search engine displays relevant results.

Using the techniques of Search Engine Optimization, site owners make an effort to improve the chances of ranking their websites high on the search engine.

There is nothing that cannot be found through some search engine.”

The search engines leverage three basic mechanisms:

  • Search Index: Search engines keep a record of all web pages online, and they are all organized to enable effective association between the page content and keyword terms. The search engine in their index grades the quality of content your webpage has.
  • Web Crawlers: Crawlers refer to the bots that browse different web pages made available to them. They collect information required to index the web page, and if it has hyperlinks, they use them to hop to other pages and index them.
  • Search Algorithms: Calculations based on which the quality of web pages are graded, figuring out if the webpage is relevant to a search term, and determining how the results are ranked based on popularity and quality of content.

Using these mechanisms, search engines deliver the most useful results to the end-users to keep coming back again.

Crawling, Indexing, and Ranking Content on Search Engines

Search Engines look simple from the outside, but a lot goes on in the backend. When a search query is typed in the search bar, you get a list of relevant pages. Search engines start their hard work even before the user searches. They work all day and night to gather information from the websites and organize them to be easy for the users to find. Finally, the results are displayed in three steps: crawling the web pages, indexing them, and ranking them in the search engines.

● Crawling:

Search engines rely on crawlers and automated scripts for scouring the web for relevant information to display results. First, they usually have a list of websites. Then, depending on different algorithms, they automatically decide which sites to crawl and display at the top. Search engine algorithms also instruct how frequently the web pages will be crawled.

From the list of websites, each site is visited by the crawlers systematically. With time, crawlers build an expanded map of all interlinked pages.

● Indexing:

SEO IndexingSEO Indexing

After the crawlers find a web page, they are fetched by the bot similarly to your browser. It means the bots see what the users can see on the web pages, including text, videos, images, or any other dynamic content. The available content on web pages is then categorized into different categories, such as HTML, CSS, text, images, etc.

It enables the crawlers to understand what is available on the page to know for which keyword that particular page needs to be displayed. The available information is then stored in an index, a huge database containing a catalog entry for each word seen on every web page.

● Ranking:

Finally, the search engine sorts all the available information and returns the right results for every query. This is done with the help of search engine algorithms to understand and analyze what a user is searching for and the results that would be most appropriate for their search.

Numerous factors help search engines define the quality of pages available in the index. An entire series of algorithms are leveraged to rank relevant results. Several ranking factors used in the algorithms analyze a piece of content for its popularity, and the qualitative experience users will have when they land on a particular webpage.

The factors that determine the quality of a webpage include:

  • Mobile-friendliness.
  • The quality of backlinks.
  • Page Speed.
  • Engagement

Google leverages the human quality raters available online to refine and test the algorithms to ensure that the algorithms are working adequately. During this test, humans, instead of programs, are involved to see how search engines work.

Relevance is the search engine’s holy grail. People want results that are closely connected to their queries.”

Leverage the Knowledge to Boost Results

Now that you know how search engines work, it will be straightforward to create websites or web pages that align with the search engine requirements. You can also easily make these pages indexable and crawlable. Then, when you send the right signals to the search engines, you are rest assured that they will get indexed and appear in the result pages whenever a search related to your business is performed.


Robots.txt files are located at the root directory of your website, and this file suggests which part of your website should be and shouldn’t be crawled by the search engines. It also depicts the speed at which your website will be crawled.

How Google Treats Robots.txt?

  • If the Googlebot does not find a robots.txt file for a particular site, it crawls the website.
  • If the Googlebot finds a robots.txt for a website, it abides by the suggestions and proceeds with the crawl.
  • If an error is encountered by the Googlebot when it tries to access the robots.txt file and cannot determine if one exists or not, the website will not be crawled.

Wrapping Up

Understanding how search engines work is the first step towards ranking the website high on the search engine. If you create web pages that are not crawlable and indexable, in other terms if search engines can’t crawl and index your web pages, you will not have any options for ranking your website on the search engine. So, if you want your website to rank on the search engine, optimize your website for SEO.

Author’s Bio:

Jennifer Goforth Gregory is a successful digital marketer with search engine optimization, creative writing, and content marketing expertise. She has helped many small and medium-sized businesses craft cost-effective digital marketing strategies and delivers outstanding results. Currently, she is doing freelance writing for SEO Experts India, a leading SEO Services Company in India.

How Do Search Engines Actually Work?

Local SEO Packages – Search Engine Optimization for Small Business Success

eCommerce FAQs

Passionate advocate for digital inclusivity, leading the charge at Understanding eCommerce to provide web accessibility solutions for businesses and organizations. Committed to making the online world accessible to all.