XML Syntax Notes
•case-sensitive
•well-formedness constraints (partial list)
–every element must have start tag and end tag
–elements must be correctly nested
–attribute values must be quoted (matching single or double)
•XML parser checks XML document to make sure that [1] it is well-formed (complies with all w.f. constraints in specification), and [2] it is valid, meaning the tag names and order conform to the XML application’s Document Type Definition (DTD)—the definition of what tags it may have and in what order