Hreflang
Hreflang tells search engines about a page's language and country versions so each user sees the right one.
How it works
Each version lists all others and itself, with "x-default" for the fallback. This site links its Turkish, English and German pages this way.
Common mistakes
Non-reciprocal links, wrong language codes and untranslated pages marked as other languages.
Frequently asked questions
Does it boost rankings?
Not directly; it shows the right page to the right user.