What is Indexing?
Storing and organizing crawled pages so they can be retrieved for queries. Indexing is selective: crawled does not mean indexed, and indexed does not mean ranking.
Related terms
Index Selection
The engine’s choice of which crawled pages to keep, favoring unique value and quality signals. Selection is why thin duplicates vanish from the index while consolidated canonicals survive.
Index Bloat
Search indexes filling with low-value URLs: facets, parameters, tag archives, thin search pages. Bloat wastes crawl budget and dilutes quality signals, so audits segment the index by template and prune deliberately.
Crawl-Render-Index Pipeline
The three stages between publishing and ranking: fetch the HTML, render resources including JavaScript, then select and store the page. Failures at different stages need different fixes, so audits must identify which stage broke.
Technical SEO
The crawling, indexing, rendering, and performance work that lets search engines reach, understand, and serve your pages. It covers directives, architecture, speed, and structured data rather than words on the page.
Crawling
How search-engine bots discover pages by following links, sitemaps, and directives. If a URL is never crawled, it cannot be indexed no matter how good its content is.
Crawl Budget
The number of pages a search engine will crawl on a site in a given period, driven by server capacity and demand signals. Large or slow sites must spend it on indexable, valuable URLs.