HTML , short for HyperText Markup Language (‘hypertext markup language’), refers to the markup language for creating web pages . It is a standard that serves as a reference for the software that connects with the development of web pages in its different versions, defines a basic structure and a code (called HTML code) for the definition of the content of a web page, such as text, images, videos. , games, among others. It is a standard in charge of the World Wide Web Consortium ( W3C ).) or WWW Consortium, an organization dedicated to the standardization of almost all the technologies linked to the web, especially with regard to its writing and interpretation. HTML is considered the most important web language and its invention was crucial in the appearance, development and expansion of the World Wide Web (WWW). It is the standard that has been imposed in the display of web pages and is the one that all current browsers have adopted.
The brett barnes language bases its development philosophy on differentiation. To add an external element to the page (image, video, script , etc.), it is not directly embedded in the page code, but a reference to the location of said element is made through text. In this way, the web page contains only text while it falls to the web browser (code interpreter) the task of joining all the elements and displaying the final page. Being a standard, HTML seeks to be a language that allows any web page written in a certain version to be interpreted in the same way (standard) by any updated web browser.
HTML is a markup language that allows us to indicate the structure of our document through tags. This language offers us great adaptability, a logical structure and is easy to interpret by both humans and machines.
However, throughout its different versions, various features have been incorporated and removed, in order to make it more efficient and facilitate the development of web pages compatible with different browsers and platforms (desktop PCs, laptops, smartphones , tablets ). , etc.) However, to correctly interpret a new version of HTML, web browser developers must incorporate these changes, and the user must be able to use the new version of the browser with the changes incorporated. Normally the changes are applied through automatic update patches ( Firefox , Chrome) or by offering a new version of the browser with all the changes incorporated, on an official download website ( Internet Explorer). Therefore, an outdated browser will not be able to correctly interpret a web page written in a higher version of HTML than it can interpret, which often forces developers to apply techniques and changes that allow correcting display problems and even interpretation of HTML code. Likewise, pages written in an older version of HTML should be updated or rewritten, which is not always the case. That is why certain browsers still maintain the ability to interpret web pages from previous HTML versions. For these reasons, there are still differences between different browsers and versions when interpreting the same web page.
Index
First HTML specifications
Tim Berners-Lee (TBL) in 1991 [ 2 ] [ 3 ] describes 18 elements that include the initial and relatively simple layout of HTML. Thirteen of these elements still exist in HTML 4. [ 4 ]
Berners-Lee considered HTML an extension of SGML , but it was not formally recognized as such until the publication in mid-1993, by the IETF (in Spanish: Internet Engineering Task Force), of a first proposal for an HTML specification. HTML: Berners-Lee and Dan Connolly ‘s Hypertext Markup Language draft , which included an SGML Document Type Definition to define the grammar. [ 5 ] The draft expired after six months, but was notable for its acknowledgment of the Mosaic browser’s own tagused to insert images without line breaks, reflecting the IETF’s philosophy of basing standards on successful prototypes. [ 6 ] Similarly, Dave Raggett’s competing draft HTML+ (Hypertext Markup Format) from late 1993 suggested standardizing already implemented features, such as tables. [ 7 ]
HTML markup
HTML is written in the form of “tags”, surrounded by angle brackets (<,>,/). HTML can also describe, to some extent, the appearance of a document, and can include or refer to a type of program called a script , which can affect the behavior of web browsers and other HTML processors. [ 8 ]
HTML is also used to refer to content of the MIME type text/html or even more broadly as a generic term for HTML, either in XML -derived form (such as XHTML 1.0 and later) or directly SGML -derived (such as HTML 4.01 and earlier). HTML consists of several vital components, including elements and their attributes , data types, and the document type declaration .
Items
Elements are the basic structure of HTML. Elements have two basic properties: attributes and content. Each attribute and content has certain restrictions for the HTML document to be considered valid. An element typically has a start tag (for example, ) and an end tag (for example, ). The element’s attributes are contained in the start tag, and the content is located between the two tags (for example, Contenido). Some elements, such as
, have no content and no closing tag. Listed below are the various types of markup elements used in HTML.
General structure of a line of code in the HTML markup language.
Structural markup describes the purpose of the text. For example,
set “Golf” as a second-level heading, which would display in a browser in a manner similar to the “HTML Bookmark” heading at the beginning of this section. Structural markup doesn’t define how the element will look, but most web browsers have standardized the formatting of elements. Specific formatting can be applied to text by means of cascading style sheets .
Presentational markup describes the appearance of text, regardless of its function. For example, negritait says that visual web browsers should display text in bold , but it doesn’t say what web browsers that display content differently (for example, those that read text aloud) should do. In the case of negritae itálica, there are elements that look the same but are more semantic in nature: énfasis fuerteand énfasis. It’s easy to see how a screen reader should interpret these two elements. However, they are equivalent to their corresponding presentational elements: a screen reader should not say the name of a book louder, even if the name stands out initalics on a screen. Most of the presentational markup has been deprecated since version 4.01, in favor of cascading style sheets.