What are some best practices for handling character encoding in PHP, specifically when working with UTF-8?

When working with UTF-8 in PHP, it is essential to ensure that your script is properly handling character encoding to avoid issues with special characters and emojis. One best practice is to set the default character encoding to UTF-8 at the beginning of your script using `mb_internal_encoding('UTF-8')`. Additionally, when working with input from forms or databases, always use functions like `mb_convert_encoding()` or `utf8_encode()` to ensure proper encoding and decoding.

// Set default character encoding to UTF-8
mb_internal_encoding('UTF-8');

// Example of converting input from a form to UTF-8
$input = $_POST['input'];
$utf8_input = mb_convert_encoding($input, 'UTF-8', 'UTF-8');

// Example of encoding output before sending to the browser
$output = "Some text with special characters 😊";
$encoded_output = utf8_encode($output);

// Example of decoding input from a database
$raw_data = $row['data'];
$decoded_data = utf8_decode($raw_data);