A search engine indexes web pages through a process known as crawling and indexing. Crawlers, or spiders, scan the web to gather information about content, links, and keywords. This data is then stored in a database, enabling the search engine to retrieve relevant pages quickly based on user queries. Proper SEO (Search Engine Optimization) practices enhance indexing efficiency and search result rankings. By analyzing content structure, links, and site performance, search engines help users find the information they require with greater accuracy.