Search engines index and retrieve information by systematically crawling and analyzing the vast content available on the web. They deploy web crawlers or bots to gather data from websites, then create an index to organize this information efficiently. When users enter a query, the search engine utilizes algorithms to evaluate the indexed content, ranking results based on relevance and quality. Factors influencing these rankings include keywords, site structure, and user engagement metrics. This efficient indexing and retrieval process ensures that users receive the most pertinent information promptly, making search engines invaluable tools for navigating the internet.