Posts Tagged ‘ XHTML

Ajax constituent technologies

Ajax uses a combination of:

  • XHTML (or HTML) and CSS, for marking up and styling information.
  • The DOM accessed with a client-side scripting language, especially ECMAScript implementations such as JavaScript and JScript, to dynamically display and interact with the information presented.
  • The XMLHttpRequest object is used to exchange data asynchronously with the web server. In some Ajax frameworks and in certain situations, an IFrame object is used instead of the XMLHttpRequest object to exchange data with the web server, and in other implementations, dynamically added <script> tags may be used.
  • XML is sometimes used as the format for transferring data between the server and client, although any format will work, including preformatted HTML, plain text and JSON. These files may be created dynamically by some form of server-side scripting.

Like DHTML, LAMP, and SPA, Ajax is not a technology in itself, but a term that refers to the use of a group of technologies.

The “core” and defining element of Ajax is the XMLHttpRequest object, which gives browsers the ability to make dynamic and asynchronous data requests without having to unload and reload a page. Given XMLHttpRequest can eliminate the need for page refreshes, other technologies have become more prominently used and highlighted with this development approach.

Besides XMLHttpRequest, the use of DOM, CSS, and JavaScript provides a more-enhanced “single-page” experience.

This guide is licensed under the GNU Free Documentation License. It uses material from the Wikipedia.

Web design

CSS Zen Garden

Web design is a process of conceptualization, planning, modeling, and execution of electronic media delivery via Internet in the form of Markup language suitable for interpretation by Web browser and display as Graphical user interface (GUI).

The intent of web design is to create a web site — a collection of electronic files that reside on a web server/servers and present content and interactive features/interfaces to the end user in form of Web pages once requested. Such elements as text, bit-mapped images (GIFs, JPEGs, PNGs), forms can be placed on the page using HTML/XHTML/XML tags. Displaying more complex media (vector graphics, animations, videos, sounds) requires plug-ins such as Flash, QuickTime, Java run-time environment, etc. Plug-ins are also embedded into web page by using HTML/XHTML tags.

Improvements in browsers’ compliance with W3C standards prompted a widespread acceptance and usage of XHTML/XML in conjunction with Cascading Style Sheets (CSS) to position and manipulate web page elements and objects. Latest standards and proposals aim at leading to browsers’ ability to deliver a wide variety of media and accessibility options to the client possibly without employing plug-ins.

Typically web pages are classified as static or dynamic.

Static pages don’t change content and layout with every request unless a human (web master/programmer) manually updates the page.

Dynamic pages adapt their content and/or appearance depending on end-user’s input/interaction or changes in the computing environment (user, time, database modifications, etc.) Content can be changed on the client side (end-user’s computer) by using client-side scripting languages (JavaScript, JScript, Actionscript, etc.) to alter DOM elements (DHTML). Dynamic content is often compiled on the server utilizing server-side scripting languages (Perl, PHP, ASP, JSP, ColdFusion, etc.). Both approaches are usually used in complex applications.

With growing specialization in the information technology field there is a strong tendency to draw a clear line between web design and web development.

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This guide is licensed under the GNU Free Documentation License. It uses material from the Wikipedia.