What is the purpose of using htmlspecialchars in PHP when fetching data from a database and displaying it in input fields?

When fetching data from a database and displaying it in input fields in PHP, it is important to use the htmlspecialchars function to prevent cross-site scripting attacks. This function converts special characters like <, >, ", ', and & into their HTML entities, ensuring that the data is displayed as plain text and not interpreted as HTML code by the browser.

// Fetch data from the database
$data = $row['column_name'];

// Display the data in an input field using htmlspecialchars
echo '<input type="text" name="input_field" value="' . htmlspecialchars($data) . '">';