Hreflang
Website and technology
Website and technology
Hreflang is the annotation that tells search engines which page belongs to which language or region, so they show the right version.
On each page you reference every language variant, including itself, plus usually an x-default for visitors outside your target languages. References must be mutual: if NL points to EN, EN must point back to NL.
Hreflang doesn't resolve duplicate content between languages — it doesn't need to — but it keeps a Belgian visitor out of your English version.