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HTML
History and evolution of HTML
CERN
World Wide Web Early 1990s
Touch Screens Frank Beck and Bent
Stumpe 1970 - 1973
Conseil Européen pour la Recherche Nucléaire (European Council for Nuclear Research)
Internet | World Wide Web
CERN - European Organization for Nuclear Research
Tim Berners-Lee – ENQUIRE - 1980 Berners-Lee specified HTML and wrote the browser
and server software in late 1990 HTML Tags – First documentation by Mr. Lee in
1991.
Hypertext and Hyperlink
In computing, a hyperlink, or simply a link, is a reference to data that the reader can directly follow either by clicking, tapping, or hovering.
The text that comes with a hyperlink is known as hypertext.
Hyperlinks in HTML
Tim Berners-Lee saw the possibility of using hyperlinks to link any information to any other information over the Internet.
Hyperlinks were therefore integral to the creation of the World Wide Web.
Web pages are written in the hypertext mark-up language HTML.
<a href="http://www.w3.org">W3C organization website</a>
1991 – A Revolutionary Year
Berners-Lee posted a short summary of the World Wide Web project on the alt.hypertext newsgroup:
“The WorldWideWeb (WWW) project aims to allow all links to be made to any information anywhere. […] The WWW project was started to allow high energy physicists to share data, news, and documentation. We are very interested in spreading the web to other areas, and having gateway servers for other data. Collaborators welcome!”
The Browser
Berners-Lee wrote the first web browser WorldWideWeb, later renamed Nexus, and released it for the NeXTstep platform
HTML
HTML is a markup language that web browsers use to interpret and compose text, images, and other material into visual or audible web pages.
A total of 18 tags were introduced in HTML 1. Influenced by Standard Generalized Markup Language
(SGML)-based documentation format at CERN
HTML Tags
<A> <ADDRESS> Base Address <DD> <DIR> <DL> <DT> <H1>...<H6> <HP!>...<HP6> <ISINDEX> <LI> <Listing> <menu>
<NEXTID>
<P>
<PLAINTEXT>
<TITLE>
<UL>
WWW-talk Mailing List
From the year 1992, web application started rolling off. A mail group was created by Tim to discuss ideas with other
researchers. A new browser was also created named Mosaic. To incorporate images, <img> tag was introduced by Marc
Andreessen from Mosaic team. HTML Working Group Lynx, a text-based browser for terminal and DOS machines.
HTML Specification
“It was very important for web to operate with a proper HTML specification.”
Evolution Overview
HTML HTML 2.0 HTML 3.2 HTML 4 XHTML HTML5
HTML 2
HTML 2.0 included everything from the original 1.0 specifications but added a few new features to the mix.
HTML 2.0 becomes the first official set of standards for HTML – the base standard by which all browsers were measured until HTML 3.2.
HTML 2.0 was used as a benchmark during the Web explosion. It introduced block structuring elements
Netscape
Mosaic Communications, later renamed Netscape Communications, releases Netscape, based on the National Center for Supercomputing Applications’ (NCSA) Mosaic browser- the 1st commercial web browser with a graphical interface.
HTML 2 Tags
<HTML> <I> <IMG> <BODY> <BR> <CAPTION> <CITE> <CODE> <COL> <COLGROUP>
<HR> <HTML> <I> <IMG> <INPUT> <!DOCTYPE> <DT> <EM> <FORM> <Table>
DOCTYPE
A document type declaration, or DOCTYPE, is an instruction that associates a particular SGML or XML document (for example, a webpage) with a document type definition (DTD) (for example, the formal definition of a particular version of HTML1.0 - HTML 4.0).
Internet Exlorer
IE 1.0 was released in August 1995
HTML 3.2 - 1997
HTML 3.2 was published as a W3C Recommendation.
HTML 3.2 Tags
<BASEFONT> <BIG> <CENTER> <DIV> <FONT> <STYLE> <SUB> <SUP> <Small> <Script>
HTML 4.01
Cougar is the code name for what becomes HTML 4.0, published as a recommendation in late 1997 and finally approved as HTML 4.01.
This version includes Cascading Style Sheets (CSS), an
easier way to control presentational elements, like colors, fonts, and backgrounds.
It removed they style related tags incorporated in Html.
HTML 4.01 Tags
<NOFRAMES> <NOSCRIPT> <OBJECT> <span> <param> <optgroup> <q> <FRAME> <FRAMESET> <ABBR> <ACRONYM> <button>
After HTML 4.01, there was no new version of HTML for many years as development of the parallel, XML-based language XHTML occupied the W3C's HTML Working Group through the early and mid-2000s.
<!DOCTYPE html><html> <head> <title>This is a title</title> </head> <body> <p>Hello world!</p> </body></html>
(The text between <html> and </html> describes the web page, and the text between <body> and </body> is the visible page content. The markup text "<title>This is a title</title>" defines the browser page title.)
SGML & XML
SGML is what is called a metalanguage; that is, a language that is used to define other languages.
To make its power available to web developers, SGML was used to create XML (eXtensible Markup Language), a simplified version, and also a metalanguage.
XHTML - 2000
The pre-existing HTML 4.01 tags and attributes were used as the vocabulary of this new Markup language, with XML providing the rules of how they are put together.
It mirrors or extends versions of the widely used Hypertext Markup Language (HTML), the language in which Web pages are formulated.
Rules
Document Structure XHTML DOCTYPE is mandatory The xmlns attribute in <html> is mandatory
<html>, <head>, <title>, and <body> are mandatory
XHTML ElementsXHTML elements must be properly nestedXHTML elements must always be closedXHTML elements must be in lowercaseXHTML documents must have one root element
XHTML AttributesAttribute names must be in lower caseAttribute values must be quotedAttribute minimization is forbidden
In October 2006, HTML inventor and W3C chair Tim Berners-Lee, said,
"The attempt to get the world to switch to XML … all at once didn't work. The large HTML-generating public did not move … Some large communities did shift and are enjoying the fruits of well-formed systems …
The plan is to charter a completely new HTML group."[38] The current HTML5 working draft says "special attention has been given to defining clear conformance criteria for user agents in an effort to improve interoperability … while at the same time updating the HTML specifications to address issues raised in the past few years."
