Interface and string translations
Now that we have our languages configured and can switch between them, we want to start viewing text in these languages. For my site, I chose Arabic, German, and Polish. By going to localize.drupal.org, you can see that these three languages are pretty well supported in Drupal because many of the core UI strings have been translated already.
Take a look to see what progress has been made for your languages. If you want to use a language that hasn't been fully translated, you can always help with the translations yourself and contribute them back to the community. That's what Drupal is all about!
In this section, we'll learn how to translate the UI using the manual process and then by leveraging the Localization ...