Imagine the internet as a gigantic library with billions of books. Each web page is like a book, and indexing is the process of organizing and cataloging these pages so that they can be easily found by search engines.
When you perform a search on Google or any other search engine, you’re essentially asking it to fetch information from its index, which is a massive database containing records of all the web pages it has crawled and deemed worthy of inclusion
https://thesecuremedia.com/what-is-indexing-in-digital-marketing