Information Technology & Communication

The World Wide Web (the “Web” or “WWW” for short) is a hypertext system that operates over the Internet. Hypertext is browsed using a program called a web browser which retrieves pieces of information (called “documents” or “web pages”) from web servers (or “web sites”) and displays them on your screen. You can then follow hyperlinks on each page to other documents or even send information back to the server to interact with it. The act of following hyperlinks is often called “surfing” the web.

Origins

The Web can be traced back to a project at CERN in 1989 when Tim Berners-Lee and Robert Cailliau built ENQUIRE (short for Enquire Within Upon Everything, a book Berners-Lee recalled from his youth). While it was rather different from the Web we use today, it contained many of the same core ideas (and even some of the ideas of Berners-Lee’s next project, the Semantic Web!). Tim Berners-Lee published a more formal proposal for the actual World Wide Web on November 12, 1990 and wrote the first web page on November 13. In Christmas of that year Berners-Lee built all the tools necessary for a working Web, the first actual web browser (which was a web-editor as well), and the first web server.

The three standards

The Web is made up of three standards: The Uniform Resource Locator (URL), which specifies how each page of information is given a unique “address” at which it can be found; Hyper Text Transfer Protocol (HTTP), which specifies how the browser and server send the information to each other, and Hyper Text Markup Language (HTML), a method of encoding the information so it can be displayed on a variety of devices. Berners-Lee now heads the World Wide Web Consortium, which develops and maintains these standards and others that enable computers on the Web to effectively store and communicate all kinds of information.

Beyond text

The initial “www” program at CERN only displayed text, but later browsers such as Pei Wei’s Viola (1992) added the ability to display graphics as well. Marc Andreessen of NCSA released a browser called “Mosaic for X” in 1993 that sparked a tremendous rise in the popularity of the Web among novice users. Andreesen went on to found Mosaic Communications Corporation (now Netscape Communications, a unit of Time Warner). Additional features such as dynamic content, music and animation can be found in modern browsers.

Frequently, the technical capability of browsers and servers advances much faster than the standards bodies can keep up with, so it is not uncommon for these newer features to not work properly on all computers, and the web as seen by Netscape is not at all the same as the web seen by Internet Explorer. The ever-improving technical capability of the WWW has enabled the development of real-time web-based services such as webcasts, web radio and live web cams.

Java and Javascript

Another significant advance in the technology was Sun Microsystems’ Java programming language, which enabled web servers to embed small programs (called applets) directly into the information being served that would run on the user’s computer, allowing faster and richer user interaction.

The similarly named, but actually quite different, JavaScript is a scripting language developed for Web pages. In conjunction with the Document Object Model, JavaScript has become a much more powerful language than its creators originally envisioned.

Sociological Implications

The exponential growth of the Internet was primarily attributed to the emergence of the web browser Mosaic, followed by another, Netscape Navigator during the mid-1990s.

It brought unprecedented attention to the Internet from media, industries, policy makers, and the general public.

Eventually, it led to several visions of how our society might change, although some point out that those visions are not unique to the Internet, but repeated with many new technologies (especially information and communications technologies) of various era.

Because the web is global in scale, some suggested that it will nurture mutual understanding on a global scale.

Statistics

By far the most Web content is in English: 56%; next are German (8%), French (6%) and Japanese (5%).

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

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.

A browser exploit is a short piece of code that exploits a software bug in a web browser such that the code makes the browser do something unexpected, including crash, read or write local files, propagate a virus or install spyware. Malicious code may exploit HTML, JavaScript, Images, ActiveX, Java and other internet technologies. HTML alone is harmless (can only crash browser in some cases on vulnerable web browsers), however, in conjunction with malicious ActiveX or Java code, it can potentially freeze or crash a browser, or even crash the computer running that browser.

The term “browser exploit” can also refer to the actual bug in the browser code.

Browser exploits families

Cross Zone Scripting exploits vulnerabilities related to the “zone” concept in some browsers; i.e. a page in “Internet zone” is able to initate execution with “Local Computer”, “Local Intranet” or “Trusted Sites” zone privileges.

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

Video: Beef Browser Exploit Framekork on BackTrack

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.

Links

• W3C – World Wide Web Consortium

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