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How Search Engine Works❓
Frequently Asked Questions
What is a search engine?
What is the most popular search engine?
What is the world wide web?
What is the internet?
What is the URL?
Last Updated: Mar 27, 2024

How Search Engine Works

Author Sanchit Kumar
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Ashwin Goyal
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The search engine is part of our daily life. Every second, someone uses a search engine to find something. We talk about search engines like Google, Bing, Yahoo, etc. But here, one might wonder how the search engine works. The answer to this question is search engines work through three primary functions; crawling, indexing and ranking. Fine! Are you ready to unfold these three primary functions related to working of search engines

how search engine works

Alright! Let us move on and see how the search engine works in detail.💫

How Search Engine Works❓

Search engines work through three primary functions.

📌Crawling - Involves searching the internet for content and reviewing the content/code for each URL they find.

📌Indexing - Involves storing and organising the content found during the crawling process.

📌Ranking - It provides the pieces of content that will be the best result to a searcher's query.

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The process of searching the internet for content and reviewing the content for each URL they find is called crawling.


Web crawlers, or internet robots, are tools that search engines use to traverse the internet to index pages systematically. These web crawlers quickly navigate between pages while reading and copying each one. Together with all the other pages, the crawler has viewed, these copies are kept in an index. The terms "crawling" and "indexing", which describe distinct steps of the same operation, can often be used interchangeably.

🔗Occasionally, your website will be crawled but not indexed; however, this typically only indicates that the crawler encountered a delay or a bug and will revisit the page. 

Although this typically implies that there was a delay or bug for the crawler, they will ultimately return to the page to index them. There are some instances where your site will be crawled but not indexed. Any updates made after a URL has been crawled twice will often be overwritten in the index.

🔥The importance of website crawling

If you wish your website to appear higher in the search results, your website must be indexed. Bots must be able to efficiently and frequently crawl your site if you want to be indexed. Even if you search for a whole paragraph that you copied and pasted from your website, if the site isn't indexed, you won't be able to find it on Google. It might as well not exist if the search engine doesn't have a duplicate of your page.


Gathering data to create an index of pages or other data is called "indexing". This data is sorted according to specific criteria, such as assigning keywords to a document based on its content. The created pages and their accompanying keywords make up the index, making it simpler to search for and sort information.


🔗Indexing is a method a search engine uses to arrange content before a search to respond to queries very quickly.

🔥If search engines had to search through every site individually for keywords and subjects, it would be difficult for them to identify relevant content. Instead, search engines (like Google) use an inverted index called a reverse index.

Inverted Index🔄

This is one of the information retrieval methods of making an index. It involves creating an inverted index of terms found in online documents. If a query contains more than one word, Google will try to return the search results consisting of all the pages that contain the union of all of the words found in a query.


When someone performs a search in the search engine, the search engines look into their index for relevant content and then order that content to solve the query of the searcher. This ordering of the search results by relevance is called "ranking". Generally, you can assume that if the website is ranked higher. The search engine believes that this website is more relevant, corresponding to that query.


🔥Crawling, indexing and discovering content is only the first part of the puzzle. When someone performs a search, search engines need a way to rank matching results. This way is the job of search algorithms. Search algorithms are formulas that rank and match relevant results from the index.

The aim of every search engine is to provide users with the best and most relevant results. We hope you understand how the search engine works.

Frequently Asked Questions

What is a search engine?

It is a tool that searches for and identifies items in a database that correspond to keywords specified by the user. It is used primarily for finding sites on the world wide web.

What is the most popular search engine?

Google is the most popular search engine.

What is the world wide web?

The world wide web is an information system that enables documents and other web resources to be accessed over the internet.

What is the internet?

It is a worldwide computer network that consists of interconnected networks using standardised communication protocols. It provides a variety of information and communication facilities.

What is the URL?

URL is the address of the webpage. It stands for uniform resource locator. 


This article discussed how the search engine works. We learnt about three primary functions through which search engine works: crawling, indexing and ranking.

We hope our blog on how the search engine works added something to your existing knowledge. You can refer to other similar articles as well - 

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Happy Learning Ninja! 🥷

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