What is XML prologue?

Expandable sign language (XML) Prologue is part of each XML system that is present in front of the root element of the system. This is part of the XML system in which XML programming information is defined. There is no standard for XML prologue, but usually contains some of the same features from one system to another. In some cases, this may even be empty because the user does not want to announce any prologue information. Even if it is empty, there is still any XML system.

XML prologue is sometimes referred to as XML statement. It is present in every system, but its use is optional. When used, it usually contains information about the version, the processing instructions, all author's comments, and the field definition fields, commonly referred to as Doctype. Sometimes it will also include transmission of information to Hypertext Markup Language (HTML) if the user wants to merge XML and HTML.

XML prologue always appears in the first part of the file. Will never follow another sectionand. The only exception is that the Bajt Order brand can be preceded by Prologue XML when certain types of character coding are used. If this is the case, the byte of the bytes order declares the type of character encoding that was used in the XML system, usually with the Unicode (UTF) transformation format. A number of character codes are available, but UTF-8 and UTF-16 are the most common and recommended coding; If there is no byte of the byte of the order, the computer reads the system as UTF-8 or UTF-16, the default coding.

processing instructions define how the application will process information within the XML Prolog and the system. Processing instructions may occur anywhere in the XML system. The XML Declaration will only be considered by the XML prologue processing instructions.

Comments such as processg information that can be found anywhere in the XML system and only comments in the prologue are considered part of the XML prologue. Comments are free text data sets that do not affect scripting within the system and usually help thereTo remember the programmer or say something to other programmers. They often contain information about the author, version number, or any other information that the author wants to pass to other scripts editors. Finally, some authors will include DOCTYPE. This is recommended, but it is still not common practice among the authors.