What are the best practices for structuring and organizing language files for multilingual websites in a CMS using PHP and MySQL?

When creating a multilingual website in a CMS using PHP and MySQL, it is important to structure and organize language files efficiently to easily manage translations. One common approach is to store language strings in separate files for each language, with a key-value pair structure for easy lookup. Using a consistent naming convention and directory structure can help keep the files organized and make it easier to add or update translations.

```php
// Example of organizing language files for a multilingual website
// Create a directory to store language files
$lang_dir = 'languages/';

// Define the current language
$current_lang = 'en';

// Include the language file based on the current language
include $lang_dir . $current_lang . '.php';

// Access language strings using keys
echo $lang['welcome_message'];
```

In this example, we create a directory called 'languages' to store our language files. Each language file is named based on the language code (e.g., 'en.php' for English). We include the language file based on the current language and access language strings using keys defined in the language file. This approach allows for easy management and organization of language files for a multilingual website.