What is search engine ?
Search Engine is a Web based Tool or Software,Which helps internet users to search information on world Wide Web.
Like- Google, Yahoo, Bing, etc are the popular search engines! that finds the data and information from the keyword and phrases to search and shows on your result page.

for example, suppose you can search on Google “what is a search engine?” so Google will match your search keyword from all the databases and websites available on the internet. And all the data related to it will show according to its search ranking on your result page.
When the user type word in search bar on google or any other search engine that is called keyword.
How Search engine works
A search engine have three primary functions to search the search by results.
And these 3 steps are as follows:
- Crawling
- Indexing
- Ranking and Retrieval

Crawling:
Crawling is the first step to search a web page. There are automatic spiders, bots, or crawlers for any search Engine, They can collect every pages and content where our keyword matched.
According to google their crawlers and bots are collects 100 to 1000 information pages in 1 second. when bots or crawlers get a new page they send it to the Back-end processing.
Indexing
Indexing comes after the process of crawling. In this process after crawling, collects all the information of web pages and database and list it by the ranking, this process is called Indexing.
Ranking and Retrieval
Ranking and Retrieval is the last and most important step for a search engine. Database and web pages collected as indexing and they are again ranked by the basis of many of their properties like Popularity, Content age, and Content keyword.
There are many algorithms for ranking and retrieval in every search engine. Because of this, our search results are correct and accurate. And whenever we do a search, we get the best result at first of the search.
Types of search engine
There are 4 types of search engine.
- Crawler-Based Search Engine
- Web Directories
- Hybrid Search Engines
- Meta Search Engines
Example of search engine
- Yahoo!
- Bing
- DuckDuckGo
- Yandex
- Ask
Conclusion:
Google, Yahoo, etc all these search engines are actually software programs, After searching whatever, the search engine gives all the information available online related to it very quickly.
All search engines work like this – Collect information, rank it by analyzing it and show results to the user.