Meaning and Main Components of a Search Engine

What is search engine?

A search engine is a coordinated set of programs that searches for and identifies items in a database that match specified criteria. Search engines are used to access information on the World Wide Web.

Source: from Tech Targets

Main Components of a Search Engine

1. Web Crawler (Spider or Bot)
   1. Function: Automatically browses the web and collects data from websites.
   1. Purpose: Finds new and updated pages to be added to the index.
2. Indexing System
   1. Function: Stores, organizes, and categorizes the content collected by crawlers.
   1. Purpose: Allows quick retrieval when a user searches for information.
3. Database
   1. Function: Holds the indexed data.
   1. Purpose: Acts as a library of web content.
4. Query Processor
   1. Function: Takes the user’s search query and interprets it.
   1. Purpose: Matches it against the index to find relevant results.
5. Ranking Algorithm
   • Function: Determines the order of search results based on relevance, quality, and other factors (like PageRank).
   • Purpose: Ensures the most useful results are shown first.
6. User Interface (UI)
   1. Function: Allows users to enter queries and view results.
   1. Purpose: Makes the search process easy and accessible.