Hypermedia systemsJakub Husár & Tomáš Jurík

ContentXHTML 2.0

Definition Short history Differences between 1.0 and 2.0 Usage suitability

ImprovementsComparison between XHTML 2.0 and

HTML 5.0Conclusion

HTML 5.0 Definition History of development Changes made from 4.01 Suitability for developers

What exactly XHTML means?

The Extensible Hypertext Markup Language, or XHTML, is a markup language that has the same depth of expression as HTML, but also conforms to XML syntax.

(Wikipedia)

XHTML History 26th January 2000

• XHTML 1.0 was published as a W3C recommendation

August 2002• W3C released first working draft of

XHTML 2.0nowadays (2008)

• expected to appear ninth working draft of XHTML 2.0

Focused on XHTML 2.0based on XMLdeveloped by the W3Creject the SGML heritage and syntax

peculiaritiespriority: separate document content

and structure from document presentation

What XHTML 2.0 consists of?XHTML 2.0 is defined as collection of modules, which, using this standard,

are creating specified types for web presentations

XHTML 2.0 vs. XHTML 1.0 tag <br /> was replaced by tag <l /> tags <b>, <big>, <i>, <small>, <tt> were removed

from presentation module; design changes are considered to be modified by CSS 2.0

tags <h1> to <h6> are gradually replaced by <section> tag

attribute name was completely replaced by attribute id

XHTML 2.0 vs. XHTML 1.0Short example of XHTML 1.0 source code

Example of XHTML 2.0 source code

Suitability for Web Developers – XHTML 2.0browser support - a crucial point for web

developersInternet Explorer doesn’t have proper

XHTML support at all + severe problems with XHTML sent as XML

there are many changes to the structure of the document

none of the major browser vendors supports XHTML 2.0

What is HTML?

HTML(an initialism of HyperText Markup Language) is the predominant markup language designed to creating Web pages and other informations presented in Web browsers.

(Wikipedia)

HTML historyNovember 1995

- HTML 2.0January 1997

- HTML 3.2December 1997

- HTML 4.0December 1999

- HTML 4.01January 2008

- HTML 5.0

Focused on HTML 5.0known also under the name Web

Applications 1.0SGML-based document formatdeveloped by the WHATWG(Web

Hypertext Application Technology Working Group)

WHATWG - open community started by three of the four major browser vendors: Mozilla, Opera, and Apple

HTML 5.0 vs. HTML 4.01syntax compatible with HTML 4.01

and XHTML 1.0defines detailed parsing rules (including "error handling")

HTML 5.0 vs. HTML 4.01new elements

e.g.: section, header, footer, audio, video, canvas …

new attributese.g.: meta element has a charset attribute …

changed meanings of some elementse.g.: b, hr, strong …

removed elementse.g.: big, center, strike …

removed attributese.g.: target attribute on link …

HTML 5.0 vs. HTML 4.01Short demonstration of HTML 5.0 source code

HTML 5.0 vs. HTML 4.01introduces a number of APIs that help in

creating Web applications2D drawing APIAPI for playing of video and audiopersistent storageAPI that enables offline Web applicationsCross-document messaging

HTML 5.0 vs. HTML 4.01Demonstration of <canvas> tag

(2D drawing API)

output:

Suitability for Web Developers – HTML 5.0turning an HTML 4.01 document

into HTML 5.0 – just question of replacing the DOCTYPE declaration

if a document doesn’t use any of the new elements or APIs introduced by HTML 5.0, the browser just sends it to its tag-soup parser

XHTML 2.0 vs. HTML 5.0increased usability and

accessibilityimproved

internationalizationmore device

independenceless scriptingbetter integration with

the Semantic Webcleaner, more concise

language - corrects many of Web markup’s past indiscretions

not so much a replacement as in XHTML2, but upgrade or evolution

aims for backwards compatibility

tries to remove undefined behavior in HTML 4.01 by defining it

semantic elements for improved form validation, interactive elements, and persistent storage

XHTML 2.0 vs. HTML 5.0XML parsing will stop at

the first error in the document

any errors will render a page totally unreachable

display only details of the error, but no content

defines exactly how this error correction is to be done

defines how parsing should work if documents are invalid, ill-formed or broken

ConclusionXHTML 2.0 is mostly only a semantic

improvement over XHTML 1.0seems like that it won’t matter for web

developers for a long time (Internet Explorer still doesn’t offer XHTML 1.0 support)

many parts of HTML 5.0 are already creeping into browsers

probably the HTML 5.0 will be the future of the web; we should pay close attention to it

Thank you for your attention

It’s time for your questions.