Transcription: You're going to hear two words quite a bit in the XML community and that is well-formed or well-formedness. I love that word. It's like they made it up, but they actually use it. Well-formedness and validity. Now these two words are often used interchangeably, but they're very separate. And what they are is they have to do with the fact of whether or not your document is actually usable by an XML. processor.