How can the use of curly braces in output affect the functionality of a PHP script?

Using curly braces in output can cause issues in a PHP script if not used properly. This is because PHP interprets variables inside curly braces as complex expressions, which can lead to unexpected behavior or errors. To avoid this, it's important to properly concatenate variables and strings without unnecessary curly braces.

// Incorrect usage of curly braces in output
$name = "John";
echo "Hello, {$name}!"; // This can cause issues

// Correct way to concatenate variables and strings
echo "Hello, " . $name . "!"; // This is the proper way to output the message