XMS Extended Memory Specification
A management and use DOS extended memory (EXTENDED MEMORY) and the high memory area (HIGH MEMORY) program specifications.

XON Communication
Standard ASCII control characters used to control the transmission of sync signals the beginning, XOFF is transmitted on behalf of the suspension.

XPath XML Path Language
Xpath is the XML family members, mainly as identification, marking a node in XML documents or elements of the use, as well as some operational strings, numbers and Boolean values (booleans) a basic function.
And XQuery, SQL and other query language is different, Xpath is only a path to be able to find the location of the node language, like hard disk folder as the file path, using a series of string, XML document to describe various elements or node position. These nodes in turn, are root, element nodes, text nodes, attribute nodes, namespace nodes, processing nodes and comment nodes functions. At present, Xpath by the same family, XSL and XML is used XPoint.

XQuery XML Query Language
XML Query, often abbreviated as XQuery, is a way for the Extensible Markup Language (XML) designed, similar to structured query language (SQL; Structured Query Language) programming language. In mid-May 2003, in the XML Query Working Group members include Microsoft, Oracle (Oracle), IBM and other companies to actively promote, the International Organization for Standardization W3C has been officially classified as a common standard XQuery. XQuery is an extension of Xpath, and XPath The difference is, XQuery offers a range of data types and control structures of the programming environment. XQuery mainly from XML documents and embedded XML database, the query or retrieve information. As has been the query SQL relational database structure, standard language, XQuery is also because it can query XML databases, but day by day become the mainstream. And even industry insiders predict that with the popularity of XML databases, XQuery will eventually replace the one day a long history of SQL language. Putting aside the future of XQuery can replace the SQL, the short term, XQuery is to make traditional database languages to interact with XML best guide. In addition, XQuery can be analyzed a large database of XML tags, so that the user may be able to easily and fully retrieval, analysis of a large number of relevant information, especially from the heterogeneous system architecture or different sources of data, and thus have the major IT vendors such as IBM , BEA and Microsoft's favor, one after another to the development of XQuery-based Information Integration (Information Integration) related technologies and products.

XSLT Extensible Stylesheet Language for Transformations
Extensible Stylesheet Language Transformations-XSLT is the XSL transformation language and the XML family. XML was originally used for general-purpose page to exchange language, appears difficult to present various forms of information, and thus develop XSLT, as the XML file be converted into other formats, such as HTML, text language of the document and is the XML technical staff in the conversion of different XML vocabulary defined in the documents, the most important tools. XSLT using the "XPath" (XML Path Language) to find the information in the XML file and its syntax can be used to point out the location of the file structure or data. Another XSLT with XSL-FO format, you can convert an object out of FO file to desktop publishing documents or classes of all kinds of books; XSLT can also be separated from the XSL-FO formatting objects, the transformation of any XML application language written in XML files. XSLT is defined by the W3C, the language of the 1.0 version of the November 16, 1999 for the first time made public.