Localization (l10n) is the process of adapting your internationalized app for a specific language or region.
Here's a step-by-step guide to implement localization in a React app:

1. Choose an i18n library
   Tools like react-i18next, formatjs, or react-intl help manage translations efficiently.

2. Set up translation files
   Create JSON files (or other formats) containing key-value pairs for each supported language. Example:

   // en.json
   {
     "welcome": "Welcome to our website!"
   }
   // fr.json
   {
     "welcome": "Bienvenue sur notre site Web!"
   }

3. Load and manage translations
   Use your i18n library to load the appropriate translation file based on the user’s selected or detected language.

4. Wrap your app with an i18n provider
   This provides the translation context across your application.

5. Replace static text with translation keys
   Instead of hardcoding text, use the translation function (t) to fetch the correct translation:

   import { useTranslation } from 'react-i18next';
   
   function HomePage() {
     const { t } = useTranslation();
     return <h1>{t('welcome')}</h1>;
   }

6. Handle fallback languages and missing keys
   Set up a fallback language (usually English) for missing translations.

7. Support dynamic language switching
   Allow users to change languages from a dropdown or menu at runtime.

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