Comments are used to hide text from the end user when the output document is displayed. They are useful as notes to the author of the document, or other authors who may modify the document.
- Comments may be placed anywhere after the XML declaration.
- Comments may not be placed inside a tag, but may be placed inside a document type declaration.
- Double dashes '--' are not allowed inside a comment.
- markup may be used inside a comment.
- Nested comments are not allowed.