The XML in LibreOffice
And how do you see that LibreOffice is XML? LibreOffice has a .xml native file format compressed. This means that the files that make up your LibreOffice document are encapsulated in an archive. An example: take your favorite unzip tool (see What is the format of LibreOffice?) and open any LibreOffice file. You will see a collection of different files, some of which have the .xml extension.