Link HREFLANG

If you work on a website that is offered in more than one language, you deserve a medal.  The need to localize almost everything is tough and sometimes feels very limiting.  No adding text to imagery, never knowing how different translation will affect layout, maintaining different templates, etc.  A very necessary task but damn, it can be tough.

Here's one easy part of localizing that's easy:  adding link elements which reference alternate URLs per language.  Here's how you'd use it:

<!-- Used on CNN -->
<link href="http://edition.cnn.com" hreflang="en-gb" rel="alternate" title="CNN International" type="text/html"/>
<link href="http://arabic.cnn.com" hreflang="ar" rel="alternate" title="CNN Arabic" type="text/html"/>
<link href="http://mexico.cnn.com" hreflang="es" rel="alternate" title="CNN Mexico" type="text/html"/>

<!-- Used on MDN -->
<link rel="alternate" hreflang="ar" href="https://developer.mozilla.org/ar/docs/Web/CSS" title="ورقة الأنماط الإنسيابية">
<link rel="alternate" hreflang="bn-BD" href="https://developer.mozilla.org/bn-BD/docs/CSS" title="CSS">
<link rel="alternate" hreflang="ca" href="https://developer.mozilla.org/ca/docs/CSS" title="CSS">
<link rel="alternate" hreflang="cs" href="https://developer.mozilla.org/cs/docs/CSS" title="CSS">
<link rel="alternate" hreflang="de" href="https://developer.mozilla.org/de/docs/Web/CSS" title="CSS">
<link rel="alternate" hreflang="es" href="https://developer.mozilla.org/es/docs/CSS" title="CSS">
<link rel="alternate" hreflang="fa" href="https://developer.mozilla.org/fa/docs/Web/CSS" title="CSS">
<link rel="alternate" hreflang="fr" href="https://developer.mozilla.org/fr/docs/CSS" title="CSS">
<link rel="alternate" hreflang="id" href="https://developer.mozilla.org/id/docs/Web/CSS" title="CSS">
<link rel="alternate" hreflang="it" href="https://developer.mozilla.org/it/docs/CSS" title="CSS">
<link rel="alternate" hreflang="ja" href="https://developer.mozilla.org/ja/docs/Web/CSS" title="CSS">
<link rel="alternate" hreflang="ko" href="https://developer.mozilla.org/ko/docs/CSS" title="CSS">
<link rel="alternate" hreflang="nl" href="https://developer.mozilla.org/nl/docs/CSS" title="CSS">
<link rel="alternate" hreflang="pl" href="https://developer.mozilla.org/pl/docs/CSS" title="CSS">
<link rel="alternate" hreflang="pt-BR" href="https://developer.mozilla.org/pt-BR/docs/CSS" title="CSS">
<link rel="alternate" hreflang="pt-PT" href="https://developer.mozilla.org/pt-PT/docs/CSS" title="CSS">
<link rel="alternate" hreflang="ru" href="https://developer.mozilla.org/ru/docs/CSS" title="CSS">
<link rel="alternate" hreflang="vi" href="https://developer.mozilla.org/vi/docs/CSS" title="CSS">
<link rel="alternate" hreflang="zh-CN" href="https://developer.mozilla.org/zh-CN/docs/CSS" title="CSS">
<link rel="alternate" hreflang="zh-TW" href="https://developer.mozilla.org/zh-TW/docs/CSS" title="CSS">

The code is very self-explanatory so I won't break it down, but it's something you should be adding when a page is available in more than one language.