Technical SEO
Putting a website in order so that search engines can find it, read it and understand it correctly.
Glossary · SEO & AI search
Technical SEO covers everything that decides whether a search engine reaches a page at all: whether it is allowed to be indexed, whether it has one clear address, whether it opens quickly, whether the content is visible without extra steps.
It is the foundation, not the whole of SEO. A technically sound site with nothing useful on it will not rise, but good content on a site with technical faults may simply never be found.
The common faults are silent: an indexing block left on by accident, the same content at several addresses, redirects broken by a redesign. The site looks fine to a visitor, so the faults are noticed only when traffic falls.