A document type definition (DTD) is a specification file that contains set of markup declarations that define a document type for an SGML-family markup language. The DTD specification file can be used to validate documents.
The HyperText Markup Language or HTML is the standard markup language for documents designed to be displayed in a web browser. It defines the meaning and structure of web content. It is often assisted by technologies such as Cascading Style Sheets (CSS) and scripting languages such as JavaScript.
Mathematical Markup Language (MathML) is a mathematical markup language, an application of XML for describing mathematical notations and capturing both its structure and content, and is one of a number of mathematical markup languages. Its aim is to natively integrate mathematical formulae into World Wide Web pages and other documents. It is part of HTML5 and standardised by ISO/IEC since 2015.
An outliner is a specialized type of text editor used to create and edit outlines, which are text files which have a tree structure, for organization. Textual information is contained in discrete sections called "nodes", which are arranged according to their topic–subtopic (parent–child) relationships, like the members of a family tree. When loaded into an outliner, an outline may be collapsed or expanded to display as few or as many levels as desired.
An HTML element is a type of HTML document component, one of several types of HTML nodes. The first used version of HTML was written by Tim Berners-Lee in 1993 and there have since been many versions of HTML. The most commonly used version is HTML 4.01, which became official standard in December 1999. An HTML document is composed of a tree of simple HTML nodes, such as text nodes, and HTML elements, which add semantics and formatting to parts of document. Each element can have HTML attributes specified. Elements can also have content, including other elements and text.
In web development, "tag soup" is a pejorative for syntactically or structurally incorrect HTML written for a web page. Because web browsers have historically treated structural or syntax errors in HTML leniently, there has been little pressure for web developers to follow published standards, and therefore there is a need for all browser implementations to provide mechanisms to cope with the appearance of "tag soup", accepting and correcting for invalid syntax and structure where possible.
OPML is an XML format for outlines. Originally developed by UserLand Software as a native file format for the outliner application in its Radio UserLand product, it has since been adopted for other uses, the most common being to exchange lists of web feeds between web feed aggregators.
An XML schema is a description of a type of XML document, typically expressed in terms of constraints on the structure and content of documents of that type, above and beyond the basic syntactical constraints imposed by XML itself. These constraints are generally expressed using some combination of grammatical rules governing the order of elements, Boolean predicates that the content must satisfy, data types governing the content of elements and attributes, and more specialized rules such as uniqueness and referential integrity constraints.
S5 is an XHTML-based file format for defining slideshows. It was created by Eric A. Meyer as an alternative to the browser-centric Opera Show Format. S5 is not a presentation program, but fulfills the same purpose in combination with a standards-compliant web browser.
XBRL is a freely available and global framework for exchanging business information. XBRL allows the expression of semantic meaning commonly required in business reporting. The standard was originally based on XML, but now additionally supports reports in JSON and CSV formats, as well as the original XML-based syntax. XBRL is also increasingly used in its Inline XBRL variant, which embeds XBRL tags into an HTML document. One common use of XBRL is the exchange of financial information, such as in a company's annual financial report. The XBRL standard is developed and published by XBRL International, Inc. (XII).
Microformats (μF) are a set of defined HTML classes created to serve as consistent and descriptive metadata about an element, designating it as representing a certain type of data. They allow software to process the information reliably by having set classes refer to a specific type of data rather than being arbitrary. Microformats emerged around 2005 and were predominantly designed for use by search engines, web syndication and aggregators such as RSS.
hCard is a microformat for publishing the contact details of people, companies, organizations, and places, in HTML, Atom, RSS, or arbitrary XML. The hCard microformat does this using a 1:1 representation of vCard properties and values, identified using HTML classes and rel attributes.
GRDDL is a markup format for Gleaning Resource Descriptions from Dialects of Languages. It is a W3C Recommendation, and enables users to obtain RDF triples out of XML documents, including XHTML. The GRDDL specification shows examples using XSLT, however it was intended to be abstract enough to allow for other implementations as well. It became a Recommendation on September 11, 2007.
RDFa or Resource Description Framework in Attributes is a W3C Recommendation that adds a set of attribute-level extensions to HTML, XHTML and various XML-based document types for embedding rich metadata within Web documents. The Resource Description Framework (RDF) data-model mapping enables its use for embedding RDF subject-predicate-object expressions within XHTML documents. It also enables the extraction of RDF model triples by compliant user agents.
The XML Bookmark Exchange Language (XBEL), is an open XML standard for sharing Internet URIs, also known as bookmarks.
Extensible HyperText Markup Language (XHTML) is part of the family of XML markup languages. It mirrors or extends versions of the widely used HyperText Markup Language (HTML), the language in which Web pages are formulated.
EPUB is an e-book file format that uses the ".epub" file extension. The term is short for electronic publication and is sometimes styled ePub. EPUB is supported by many e-readers, and compatible software is available for most smartphones, tablets, and computers. EPUB is a technical standard published by the International Digital Publishing Forum (IDPF). It became an official standard of the IDPF in September 2007, superseding the older Open eBook (OEB) standard.
A link relation is a descriptive attribute attached to a hyperlink in order to define the type of the link, or the relationship between the source and destination resources. The attribute can be used by automated systems, or can be presented to a user in a different way.
XHTML+RDFa is an extended version of the XHTML markup language for supporting RDF through a collection of attributes and processing rules in the form of well-formed XML documents. XHTML+RDFa is one of the techniques used to develop Semantic Web content by embedding rich semantic markup. Version 1.1 of the language is a superset of XHTML 1.1, integrating the attributes according to RDFa Core 1.1. In other words, it is an RDFa support through XHTML Modularization.
