Glossary
Sitemap
A sitemap is a file listing the pages on your site that you want search engines to find and index.
It lives at a fixed address, usually /sitemap.xml, and is normally declared in robots.txt so crawlers find it without being told. Most modern site builders generate one automatically.
Why it matters to you
It does not make pages rank. It makes them discoverable, which matters most for new sites and for pages nothing else links to.
An example
Submitting a sitemap in Search Console turns indexing from something you wait for into something you can watch, with a report of what was accepted and what was not.
Where this comes up: search engine optimisation .