XSD File Extension

XSD file contains formal description of XML document elements – data definitions saved in XML text format. XSD file contains set of rules which a XML files must follow to be considered a proper XML file. The file doesn’t have an unique Internet Media Type identifire as it is the same type as XML - ‘a pplication/xml’ or ‘ text/xml’. XSD file can have its data organized into so called namespaces. Main schema components are:

• Element declarations,
• Attribute declarations,
• Data types – simple or complex, based on restrictions, selection list, or primitive types,
• Macros, that is reusable groups of elements or attributes,

XSD specification was developed in 2001 with the help of W3C (World Wide Web Consortium) organization. XSD format offers more features than similar DTD document defi n ition format. XSD specification document is divided into 3 parts:

• Part 0. Primer – contains general description of the standard and basics, commonly consulted by less technical users working with XSD,
• Part 1. Structures,
• Part 2. Datatypes.

Parts 1 and 2 are many pages long and written in technical language. Second version of the specification was released in 2004, and XSD 1.1 has been approved by W3C in 2012. XSD files are used for storing metadata for XML documents, but they can also by used by developers for generating code or document descriptions in human-readable form.