How Search Engines work

What is a Search Engine?
A Search Engine is a computer program that collects and organizes content from across the internet.

The Search Engine performs three tasks:

• Crawling
• Indexing
• Ranking

Crawling: Crawling is the process by which search engines dispatch a team of robots (called crawlers or spiders) to find new and updated content. Content can take many forms — a webpage, an image, a video, a PDF, or anything else — but it is found through links.

By following this path of links, the crawler can discover new content and add it to their index called Caffeine (a massive database of discovered URLs) to be retrieved later when a searcher is looking for information on that content URL is a good match.

Indexing: Search engines process and store information they discover in an index, which is a massive database of all the content they've discovered and deemed suitable for serving to searchers.

Ranking: When someone conducts a search, search engines scour their index for highly relevant content, which is then ordered in the hopes of answering the searcher's query. Ranking refers to the ordering of search results based on relevance. In general, the higher a website ranks, the more relevant the search engine believes that website is to the query.

References

https://turbofuture.com/internet/What-is-a-Search-Engine-Definition-and-Examples

https://moz.com/beginners-guide-to-seo/how-search-engines-operate