Indexing
Indexing is the step where a search engine adds a crawled page to its searchable database so it can rank for queries. Only pages that return 200 and are not blocked get indexed; pages behind errors, redirects, or noindex rules do not.
Related terms
Crawl budget
How many of a site's URLs a search engine will crawl in a given period.
Canonical URL
The version of a page you tell search engines to treat as the original.
robots.txt
A file telling crawlers which parts of a site they may or may not crawl.
Sitemap
An XML file listing a site's URLs to help search engines find them.