What are some potential pitfalls of using PHP to output data through a TextArea element?

One potential pitfall of using PHP to output data through a TextArea element is that if the data contains characters that are interpreted as HTML tags, it can lead to unintended formatting or even security vulnerabilities like cross-site scripting (XSS). To prevent this, you can use the htmlspecialchars() function in PHP to escape special characters before outputting the data.

<textarea><?php echo htmlspecialchars($data); ?></textarea>