Index

Index (and indexing) in the digital world usually refers to creating a structured list of data that makes things faster to find — kind of like a smart table of contents for computers.

The term “index” comes from Latin index, meaning “pointer” — and that’s exactly what it does. In search engines, indexing means scanning and storing web pages in a massive database so they can show up in search results. In databases, an index helps speed up queries by pointing directly to the rows you need, rather than searching the whole table.

Let’s break it down. Imagine a library with no catalog: finding one book would take forever. Now imagine a card catalog (old-school) or a search bar (modern) that helps you instantly locate any book by title, author, or subject. That catalog is an index. Google does this at web scale: it crawls websites and builds a gigantic index of what’s on them, so you can Google “best empanada recipe” and get instant results.

Indexing also shows up in coding (like arrays or data structures), where an “index” tells you the position of an item — think of it like seat numbers in a stadium.

Curious about how Google indexing works? Here’s Google’s guide on crawling and indexing.