XML is a markup language that can be used to encapsulate any type of data that is transmitted over the network or stored on a disk. By definition, the format is generic (extensible) and does not automatically indicate the type of data that it contains. We have to create the format. In this sense XML is a self-descriptive language.
The document always starts with a directive telling the XML parser that the file is indeed XML. The directive also tells the parser the version and optionally the encoding type of the data. Encoding type is the format in which each character in the file is stored.
XML documents always consist ...