How can the use of the "&" symbol in PHP links affect the functionality of the code?

Using the "&" symbol in PHP links can interfere with the functionality of the code because it is typically used as a separator for query parameters in URLs. To avoid this issue, it is recommended to use the "&" entity instead, which represents the "&" symbol in HTML.

$url = 'https://example.com/page.php?param1=value1&param2=value2';
echo '<a href="' . $url . '">Link</a>';