Web Technologies

Web Technologies

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Internet Architecture

• Distributed computing• No central authority• Client-Server Architecture• Possible to connect almost any device to

network• TCP/IP – Transmission Control Protocol / Internet Protocol

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Internet Protocol (IP)

• Packet structure• Uniform Resource Locator (URL)• Domain Name Service• IPV6– Larger address space– Better security– Faster routing– Multicasting

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Hyper Text Markup Language(HTML)

• Is the basic building-blocks of webpages. • A markup language is a set of hidden tags to

describe page formatting.• Content + HTML web page.• http://www.geneseo.edu

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Cascading Style Sheets(CSS)

• Used to describe the presentation semantics (the look and formatting) of a document– Is designed primarily to enable the separation of

document content (written in HTML or a similar markup language) from document presentation, including elements such as the layout, colors, and fonts

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DHTML

• Dynamic HTML• Allows scripting languages to change variables

in a web page's definition language, which in turn affects the look and function of otherwise "static" HTML page content, after the page has been fully loaded and during the viewing process.

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DHTML Uses

• Animate text and images in their document, independently moving each element from any starting point to any ending point, following a predetermined path or one chosen by the user.

• Embed a ticker that automatically refreshes its content with the latest news, stock quotes, or other data.

• Use a form to capture user input, and then process and respond to that data without having to send data back to the server.

• Include rollover buttons or drop-down menus.

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Extensible Markup Language (XML)

• Is a set of rules for encoding documents in machine-readable form.

• Design goals emphasize simplicity, generality, and usability over the Internet.

• Although the design of XML focuses on documents, it is widely used for the representation of arbitrary data structures.

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eXtensible HyperText Markup Language(XHTML)

• Was developed to make HTML more extensible and increase interoperability with other data formats.[

• More rigorous HTML

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Flash

• Is a multimedia platform used to add animation, video, and interactivity to web pages.

• Is frequently used for advertisements and games.

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HTML 5

• Improve the language with support for the latest multimedia.

• Keeps it easily readable by humans.• Consistently understood by computers. • HTML5 is intended to subsume not only

HTML 4, but XHTML 1.• Replacement for Flash.

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JavaScript

• Client-side scripting language for web pages.• Used to add interactivity to web pages.• Enhanced user interface.

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Apache

• Is web server software notable for playing a key role in the initial growth of the World Wide Web.

• In 2009 it became the first web server software to surpass the 100 million web site milestone.

• Open source

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PHP

• PHP: Hypertext Preprocessor (a recursive acronym, originally personal home page)

• PHP is a general-purpose scripting language that was originally designed for web development to produce dynamic web pages.

• Others: Ruby, ColdFusion, Perl, Python.

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mySQL

• My Structured Query Language• Is a relational database management system

(RDBMS).• Provides multi-user access to a number of

databases.

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Web 2.0

• Allows users to interact and collaborate with each other in a social media dialogue as consumers of user-generated content in a virtual community.

• Basically refers to the transition from static HTML Web pages to a more dynamic Web that is more organized and is based on serving Web applications to users

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Web 2.0 Features(SLATES)

• Search: Finding information through keyword search. • Links: Connects information together into a meaningful information ecosystem

using the model of the Web, and provides low-barrier social tools. • Authoring : The ability to create and update content leads to the collaborative

work of many rather than just a few web authors. In wikis, users may extend, undo and redo each other's work. In blogs, posts and the comments of individuals build up over time.

• Tags: Categorization of content by users adding "tags" - short, usually one-word descriptions - to facilitate searching, without dependence on pre-made categories. Collections of tags created by many users within a single system may be referred to as "folksonomies" (i.e., folk taxonomies).

• Extensions: Software that makes the Web an application platform as well as a document server. These include software like Adobe Reader, Adobe Flash player, Microsoft Silverlight, ActiveX, Oracle Java, Quicktime, Windows Media, etc.

• Signals: The use of syndication technology such as RSS to notify users of content changes.

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Web 2.0

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Asynchronous JavaScript and XML (Ajax),

• Is a group of interrelated web development methods used on the client-side to create interactive web applications.

• Web applications can retrieve data from the server asynchronously in the background without interfering with the display and behavior of the existing page.

• Ajax is not one technology, but a group of technologies.

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Web 3.0

• Semantic Web is a group of methods and technologies to allow machines to understand the meaning – or "semantics" – of information on the World Wide Web.

• Web pages are personalized based on the characteristics (interests, social category, context, ...) of an individual.

• The computer is generating new information, rather than humans

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Metaverse

• Convergence of the virtual and physical world.• Includes TV-quality open video, 3D

simulations, pervasive broadband, wireless, and sensors. (Pervasive computing)

• Geospatial (Foursquare)• Augmented reality (Google Goggles)