Hyper Text Markup Language
You might not believe it, but the Net's roots are in the 1960´s. The RAND Corporation, America's foremost Cold War thinking machine, faced a strategic problem. How could the US authorities successfully communicate after a nuclear attack? So scientists began to construct a network. This was the beginning of the internet. It was called ARPANET because the Pentagon's Advanced Research Projects Agencs (ARPA) had installed it. In 1972 Ray Tomlinson of BBN invented the first e-mail program.
In 1983 the ARPANET split into ARPANET and the military segment, MILNET. The ARPANET kept growing during the early eighties. In 1984 the number of hosts broke 1000, in 1987 they broke 10,000 and in 1989 the even broke 100,000. In 1992 the World Wide Web (WWW) was released and the number of hosts broke 1,000,000.
The WWW was invented at CERN, an institute for particle physics situated in Switzerland. Originally, WWW was developed only for high energy physics.
Tim Berners - Lee was the driving force behind the development. He wrote the first WWW client and the first WWW server and defined standards such as URL, HTML and HTTP while working at CERN.
Before HTML there were thousands of word processing programs out on the market. Each of it encoded text in a different way when it saved data to a disk. This made it impossible to create a single text file that could be viewed by every operating system. So it was necessary to define a standard. This standard is the Standard Generalized Markup Language (SGML). HTML is a sub-language of the SGML just as VRML and XML. Note that HTML in not a programming language! It only describes formatting and hypertext links, and it defines different components of a document.
Who can make a standard like the SGML or the HTML for the internet? The internet is very neutral. That means that there is no matter what country you live in, what language you speak or what operating system you are running. The internet isn't anchored to any specific nation. No government can define a standard for all nations on earth. Thousands of corporations are developing technology for the internet. Giving such power to any one company would raise serious legal concerns about monopolisation and unfair business practices. Only an organisation that is not tied by any one government or business can make such standard.
The World Wide Web Consotium (W3C) is such an organisation. Founded in 1994 and hosted in the United States, in Europe and in Asia, this organisation is charged with developing and publishing standards for the World Wide Web.
These standards are not laws. They are guidelines for web-designers to make their products compatible with all systems of potential customers.
So far there are six different versions of HTML:
First Tim Berners-Lee wrote HTML 1.0 with its own Browser in 1990. Over the next couple of months, several other web-browsers began to support this language. Few of these browsers defined the language in the same way, which resulted in a fracturing of the language into dozens of variants. For years several standards groups tried to solidify the language.
In 1993 a proposal was made for a new HTML standard called HTML +. But it was never ratified.
HTML 2.0 was the first version that became to a standard. It was released in 1995 and was the first one that supported images and forms.
Two new browsers fully supported HTML 2.0:
Netscape's Navigator 2.0 and
Microsoft's Internet Explorer 2.0
After developers noticed shortcomings in the flexibility of HTML 2.0 they began to develop a successor. Much of HTML 3.0 came from the failed HTML +. But it failed, because the changes between HTML 2.0 and 3.0 were so many that upgrading the browsers was not cost effective.
Several browsers began to support proprietary tags to enhance the flexibility of the language. But the main purpose of the language was to provide a universal language for the publishing of documents on the internet. So the W3C organised a committee to develop the next revision of the language. HTML 3.2 was an amalgam of HTML 2.0 and HTML 3.0. It was supported by all major browsers.
HTML 4.0 is the latest version of HTML. It became a standard on December 18th 1997. The differences of HTML 3.2 and HTML 4.0 are a few new features. With these features the coding of a web site will be limited only to the imagination of the site developer.
If end users are accessing a web site that uses HTML tags that aren't supported by their browser, there will typically not be any error message. The web site will be missing an image or component, or the user will see the page in a different format.
So, since the internet is expanding, different people and organisations are trying to develop a standard for publishing documents on the web. There are six generations of HTML. They all have got the same purpose. But there are differences in the compilation of HTML between the biggest browsers, the Microsoft Explorer and the Netscape Navigator. So the goal isn't reached. And I think there is still a lot of work to do.
Ultimele referate adaugate
- Mihai beniuc - „poezii"
- Mihai eminescu - student la berlin
- Mircea Eliade - Mioara Nazdravana (mioriţa)
- Chirita in provintie de Vasile Alecsandri -expunerea subiectului
- Dragoste de viata de Jack London
|Ion Luca Caragiale
- Triumful talentului… (reproducere) de Ion Luca Caragiale
- Fantasticul in proza lui Mircea Eliade - La tiganci
- „Personalitate creatoare” si „figura a spiritului creator” eminescian
- Enigma Otiliei de George Calinescu - geneza, subiectul si tema romanului
- Arta literara in romanul Ion, - Liviu Rebreanu