Characters can be escaped using character references, in element content or attribute values. Their Unicode codepoint can be specified in decimal or hex.
<?xml version="1.0"?> <document> The line feed character can be escaped with a decimal ( ) or hex (
) representation of its Unicode codepoint (10). </document>
XML restricts characters that can appear in a document, even escaped. In particular, the only control characters allowed are line feed (10), carriage return (13) or horizontal tab (9).