What do comments look like in XML? Comments in XML begin with <!-- and end with -->. For example: <!-- This is a comment -->. The string "--" (double-hyphen) must not occur within comments. Can an attribute be repeated in the same element? No. An attribute name must not appear more than once in the same start-tag or empty-element tag. Where is it stated that tag names must match?
Section 3.1
The W3C recommendation states that the Name in the end-tag must match that in the start-tag. XML is case-sensitive, meaning "Tag" and "tag" are different.