How Do Search Engines Work?
As shown in the main figure, we can explain how search engines work from two perspectives.
How do search engines work from the user's point of view?
From the user's point of view, the way search engines work is very simple.
First, a user enters a Search Query (a specific set of words or phrases entered into a search engine to find information).
Second, the user will get the search results on the SERP (Search Engine Result Page).
Note: SERP (Search Engine Result Page)
SERPs do not only display organic search results with text and URLs.
Nowadays, SERPs show information related to the searched keywords in various formats. Here are examples of the key forms of information on SERPs.
The image above illustrates an example of SERP. The main part of SERP is Organic Search Results. Google's ranking algorithm orders the results, considering several factors. We'll explain the ranking algorithm later in this learning section.
The Google Ads platform also connects with SERPs. If advertisers bid on the searched keywords, Paid Ads (marked as "Sponsored") may appear below the search bar.
The SERP may also display several Featured Rich Results.
To learn more about these results, check Chapter 12. Implementing Schema Markup.
How do search engines work behind the scenes?
While the search engine looks very simple from the user's perspective, Google does a lot of work behind the scenes.
Here are the simplified explanations of the search engine mechanism:
Crawling
First, Google uses automated bots (called crawlers or Googlebots). These bots regularly and systematically browse web pages on the internet across the world to collect and assess the information each web page provides.
Indexing
The content of the crawled pages is parsed (analyzed). Then, the relevant text content is extracted from the parsed information and added to Google's index, a massive database that stores details about the content and structure of web pages.
Ranking Algorithms
When a user enters a search query, the search engine uses a ranking algorithm to evaluate and rank the indexed pages based on various factors.
To understand how the Google search engine works, check Google's official documentation – In-depth guide to how Google Search works.
You can also learn this topic offline. Click 
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