Web Browser

A Web browser is a software application which enables a user to display and interact with text, images, videos, music, games and other information typically located on a Web page at a Web site on the World Wide Web or a local area network.

Text and images on a Web page can contain hyperlinks to other Web pages at the same or different Web site. Web browsers allow a user to quickly and easily access information provided on many Web pages at many Web sites by traversing these links. Web browsers format HTML information for display, so the appearance of a Web page may differ between browsers.

Web browsers are the most-commonly-used type of HTTP user agent. Although browsers are typically used to access the World Wide Web, they can also be used to access information provided by Web servers in private networks or content in file systems.

HISTORY
The history of the Web browser dates back to late 1980s, when a variety of technologies laid the foundation for the first Web browser, the WorldWideWeb, by Tim Berners-Lee in 1991. That browser brought together a variety of existing and new software and hardware technologies.

Over the following years, Web browsers were introduced by companies like Mozilla, Netscape, Microsoft, Apple, and Opera. More recently, Google entered the browser market.

CURRENT WEB BROWSERS
Some of the Web browsers currently available for personal computers include Internet Explorer, Mozilla Firefox, Safari, Opera, Avant Browser, Konqueror, Lynx, Google Chrome, Maxthon, Flock, Arachne, Epiphany, K-Meleon and AOL Explorer.

PROTOCOLS & STANDARDS
Web browsers communicate with Web servers primarily using Hypertext Transfer Protocol (HTTP) to fetch Web pages. HTTP allows Web browsers to submit information to Web servers as well as fetch Web pages from them.

The most-commonly-used version of HTTP is HTTP/1.1, which is fully defined in RFC 2616. HTTP/1.1 has its own required standards that Internet Explorer does not fully support, but most other current-generation Web browsers do.

Pages are located by means of a URL (Uniform Resource Locator, RFC 1738), which is treated as an address, beginning with http: for HTTP transmission.

Many browsers also support a variety of other URL types and their corresponding protocols, such as gopher: for Gopher (a hierarchical hyperlinking protocol), ftp: for File Transfer Protocol (FTP), rtsp: for Real-time Streaming Protocol (RTSP), and https: for HTTPS (HTTP Secure, which is HTTP augmented by Secure Sockets Layer or Transport Layer Security).

The file format for a Web page is usually HTML (HyperText Markup Language) and is identified in the HTTP protocol using a MIME content type. Most browsers natively support a variety of formats in addition to HTML, such as the JPEG, PNG and GIF image formats, and can be extended to support more through the use of plugins.

The combination of HTTP content type and URL protocol specification allows Web-page designers to embed images, animations, video, sound, and streaming media into a Web page, or to make them accessible through the Web page.

Early Web browsers supported only a very simple version of HTML. The rapid development of proprietary Web browsers led to the development of non-standard dialects of HTML, leading to problems with Web interoperability.

Modern Web browsers support a combination of standards-based and de facto HTML and XHTML, which should be rendered in the same way by all browsers.
No browser fully supports HTML 4.01, XHTML 1.x or CSS 2.1 yet. Many sites are designed using WYSIWYG HTML-generation programs such as Adobe Dreamweaver or Microsoft FrontPage.

Microsoft FrontPage often generates non-standard HTML by default, hindering the work of the W3C in promulgating standards, specifically with XHTML and Cascading Style Sheets (CSS), which are used for page layout.
Dreamweaver and other more modern Microsoft HTML development tools such as Microsoft Expression Web and Microsoft Visual Studio conform to the W3C standards.

Some of the more popular browsers include additional components to support Usenet news, Internet Relay Chat (IRC), and e-mail. Protocols supported may include Network News Transfer Protocol (NNTP), Simple Mail Transfer Protocol (SMTP), Internet Message Access Protocol (IMAP), and Post Office Protocol (POP).
These browsers are often referred to as "Internet suites" or "application suites" rather than merely Web browsers.


Source: en.wikipedia.org

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Web Portal

A web portal presents information from diverse sources in a unified way. Apart from the search engine standard, web portals offer other services such as e-mail, news, stock prices, infotainment, and other features.

Portals provide a way for enterprises to provide a consistent look and feel with access control and procedures for multiple applications, which otherwise would have been different entities altogether. An example of a web portal is MSN.

HISTORY
In the late 1990s the web portal was a hot commodity. After the proliferation of web browsers in the mid-1990s many companies tried to build or acquire a portal, to have a piece of the Internet market. The web portal gained special attention because it was, for many users, the starting point of their web browser.

Netscape became a part of America Online, the Walt Disney Company launched Go.com, and Excite and @Home became a part of AT&T during the late 1990s. Lycos was said to be a good target for other media companies such as CBS.

Many of the portals started initially as either web directories (notably Yahoo!) or search engines (Excite, Lycos, AltaVista, infoseek, Hotbot were among the earliest). Expanding services was a strategy to secure the user-base and lengthen the time a user stayed on the portal.

Services which require user registration such as free email, customization features, and chatrooms were considered to enhance repeat use of the portal. Game, chat, email, news, and other services also tend to make users stay longer, thereby increasing the advertising revenue.

The portal craze, with "old media" companies racing to outbid each other for Internet properties, died down with the dot-com flameout in 2000 and 2001. Disney pulled the plug on Go.com, Excite went bankrupt and its remains were sold to iWon.com. Some portal sites such as Yahoo! remain successful. Added Now..........


KINDS OF PORTAL
Two broad categorizations of portals are Horizontal portals (e.g. Yahoo) and Vertical portals (or vortals, focused on one functional area, e.g. salesforce.com).

"Personal portals"
A personal portal is a site on the World Wide Web that typically provides personalized capabilities to its visitors, providing a pathway to other content.

It is designed to use distributed applications, different numbers and types of middleware and hardware to provide services from a number of different sources.

In addition, business portals are designed to share collaboration in workplaces. A further business-driven requirement of portals is that the content be able to work on multiple platforms such as personal computers, personal digital assistants (PDAs), and cell phones/mobile phones.
A personal or web portal can be integrated with many forum systems.

"Regional web portals"
Along with the development and success of international personal portals such as Yahoo!, regional variants have also sprung up. Some regional portals contain local information such as weather forecasts, street maps and local business information.

Another notable expansion over the past couple of years is the move into formerly unthinkable markets.

"Local content - global reach" portals have emerged not only from countries like Korea (Naver), India (Rediff), China (Sina.com), Romania (Neogen.ro), Greece (in.gr) and Italy (Webplace.it), but in countries like Vietnam where they are very important for learning how to apply e-commerce, e-government, etc. Such portals reach out to the widespread diaspora across the world.

"Government web portals"
At the end of the dot-com boom in the 1990s, many governments had already committed to creating portal sites for their citizens. In the United States the main portal is USA.gov in English and GobiernoUSA.gov in Spanish, in addition to portals developed for specific audiences such as DisabilityInfo.gov; in the United Kingdom the main portals are Directgov (for citizens) and businesslink.gov.uk (for businesses).

Many U.S. states have their own portals which provide direct access to e-commerce applications, agency and department web sites, and more specific information about living in, doing business in and getting around the state. Some U.S. states have chosen to out-source the operation of their portals to third-party vendors.

The National Portal of India provides comprehensive information about India and its various facets.

One of the issues that come up with government web portals is that different agencies often have their own portals and sometimes a statewide portal-directory structure is not sophisticated and deep enough to meet the needs of multiple agencies.

"Corporate web portals"
Corporate intranets became common use during the 1990s. Having access to company information via a web browser ushered in new way of working. As intranets grew in size and complexity, webmasters were faced with increasing content and user management challenges.

A consolidated view of company information was judged insufficient, users wanted personalization and customization. Webmasters, if skilled enough, were able to offer some capabilities, but for the most part ended up driving users away from using the intranet.

Many companies began to offer tools to help webmasters manage their data, applications and information more easily, and through personalized views. Some portal solutions today are able to integrate legacy applications, other portals objects, and handle thousands of user requests.

Today’s corporate portals offer extended capabilities for businesses: workflow management, collaboration between work groups, and policy-managed content publication.
In addition, most portal solutions today can allow internal and external access to specific corporate information using secure authentication or Single sign-on.

JSR168 Standards emerged around 2001. Java Specification Request (JSR) 168 standards allow the interoperability of portlets across different portal platforms. These standards allow portal developers, administrators and consumers to integrate standards-based portals and portlets across a variety of vendor solutions.

The concept of content aggregation seems to still gain momentum and portal solution will likely continue to evolve significantly over the next few years. The Gartner Group predicts generation 8 portals to expand on the enterprise mash-up concept of delivering a variety of information, tools, applications and access points through a single mechanism.

With the increase in user generated content, disparate data silos, and file formats, information architects and taxonomist will be required to allow users the ability to tag (classify) the data. This will ultimately cause a ripple effect where users will also be generating ad hoc navigation and information flows.

Some useful lessons can be learned from web 2.0 applications such as Netvibes, PageFlakes, Protopage and a new breed of competitors, such as PersonAll, use this angle to enter the market.

"Hosted web portals"
As corporate portals gained popularity a number of companies began offering them as a hosted service. The hosted portal market fundamentally changed the composition of portals. In many ways they served simply as a tool for publishing information instead of the loftier goals of integrating legacy applications or presenting correlated data from distributed databases.

The early hosted portal companies such as Hyperoffice.com or the now defunct InternetPortal.com focused on collaboration and scheduling in addition to the distribution of corporate data. As hosted web portals have risen in popularity their feature set has grown to include hosted databases, document management, email, discussion forums and more.

Hosted portals automatically personalize the content generated from their modules to provide a personalized experience to their users. In this regard they have remained true to the original goals of the earlier corporate web portals.

"Domain-specific portals"
A number of portals have come about that are specific to the particular domain, offering access to related companies and services, a prime example of this trend would be the growth in property portals that give access to services such as estate agents, removal firm, and solicitors that offer conveyancing.

A number of portals have come about that are specific to the particular domain, offering access to related companies and services. Along the same lines, industry-specific news and information portals have appeared.

"Sports portals"
Web portals have also expanded into the professional sports market. Fans of sports teams create a Sportal (sports portal), which brings all information about a professional sports team to one web portal.


Source: en.wikipedia.org

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Website

A web site is a collection of Web pages, images, videos or other digital assets that is hosted on one or more web servers, usually accessible via the Internet.

A Web page is a document, typically written in (X)HTML, that is almost always accessible via HTTP, a protocol that transfers information from the Web server to display in the user's Web browser.



A web site is a collection of Web pages, images, videos or other digital assets that is hosted on one or more web servers, usually accessible via the Internet.

A Web page is a document, typically written in (X)HTML, that is almost always accessible via HTTP, a protocol that transfers information from the Web server to display in the user's Web browser.

All publicly accessible websites are seen collectively as constituting the "World Wide Web".
The pages of a website can usually be accessed from a common root URL called the homepage, and usually reside on the same physical server.

The URLs of the pages organize them into a hierarchy, although the hyperlinks between them control how the reader perceives the overall structure and how the traffic flows between the different parts of the site.

Some websites require a subscription to access some or all of their content. Examples of subscription sites include many business sites, parts of many news sites, academic journal sites, gaming sites, message boards, Web-based e-mail, services, social networking websites, and sites providing real-time stock market data. Because they require authentication to view the content they are technically an Intranet site.


HISTORY
The World Wide Web was created in 1990 by CERN engineer, Tim Berners-Lee. On 30 April 1993, CERN announced that the World Wide Web would be free to anyone.

Before the introduction of HTML and HTTP other protocols such as file transfer protocol and the gopher protocol were used to retrieve individual files from a server.

These protocols offer a simple directory structure which the user navigates and chooses files to download. Documents were most often presented as plain text files without formatting or were encoded in word processor formats.


OVERVIEW
Organized by function a website may be:

• a personal website
• a commercial website
• a government website
• a non-profit organization website
  

It could be the work of an individual, a business or other organization, and is typically dedicated to some particular topic or purpose. Any website can contain a hyperlink to any other website, so the distinction between individual sites, as perceived by the user, may sometimes be blurred.

Websites are written in, or dynamically converted to, HTML (Hyper Text Markup Language) and are accessed using a software interface classified as an user agent. Web pages can be viewed or otherwise accessed from a range of computer-based and Internet-enabled devices of various sizes, including desktop computers, laptops, PDAs and cell phones.

A website is hosted on a computer system known as a web server, also called an HTTP server, and these terms can also refer to the software that runs on these systems and that retrieves and delivers the Web pages in response to requests from the website users.
Apache is the most commonly used Web server software (according to Netcraft statistics) and Microsoft's Internet Information Server (IIS) is also commonly used.


WEBSITE STYLE

"Static Website"
A Static Website is one that has web pages stored on the server in the same form as the user will view them. It is primarily coded in HTML (Hyper-text Markup Language).

A static website is also called a Classic website, a 5-page website or a Brochure website because it simply presents pre-defined information to the user. It may include information about a company and its products and services via text, photos, Flash animation, audio/video and interactive menus and navigation.

This type of website usually displays the same information to all visitors, thus the information is static. Similar to handing out a printed brochure to customers or clients, a static website will generally provide consistent, standard information for an extended period of time.

Although the website owner may make updates periodically, it is a manual process to edit the text, photos and other content and may require basic website design skills and software.

In summary, visitors are not able to control what information they receive via a static website, and must instead settle for whatever content the website owner has decided to offer at that time.

They are edited using four broad categories of software:

• Text editors, such as Notepad or TextEdit, where the HTML is manipulated directly within the editor program
• WYSIWYG offline editors, such as Microsoft FrontPage and Adobe Dreamweaver (previously Macromedia Dreamweaver), where the site is edited using a GUI interface and the underlying HTML is generated automatically by the editor software
• WYSIWYG Online editors, where the any media rich online presentation like websites, widgets, intro, blogs etc. are created on a flash based platform.
• Template-based editors, such as Rapidweaver and iWeb, which allow users to quickly create and upload websites to a web server without having to know anything about HTML, as they just pick a suitable template from a palette and add pictures and text to it in a DTP-like fashion without ever having to see any HTML code.
  

"Dynamic website"
A Dynamic Website is one that does not have web pages stored on the server in the same form as the user will view them.
Instead, the web page content changes automatically and/or frequently based on certain criteria. It generally collates information on the hop each time a page is requested.

A website can be dynamic in one of two ways. The first is that the web page code is constructed dynamically, piece by piece. The second is that the web page content displayed varies based on certain criteria. The criteria may be pre-defined rules or may be based on variable user input.

The main purpose behind a dynamic site is that it is much simpler to maintain a few web pages plus a database than it is to build and update hundreds or thousands of individual web pages and links.

In one way, a data-driven website is similar to a static site because the information that is presented on the site is still limited to what the website owner has allowed to be stored in the database (data entered by the owner and/or input by users and approved by the owner).

The advantage is that there is usually a lot more information stored in a database and made available to users. A dynamic website also describes its construction or how it is built, and more specifically refers to the code used to create a single web page.

A Dynamic Web Page is generated on the fly by piecing together certain blocks of code, procedures or routines. A dynamically-generated web page would call various bits of information from a database and put them together in a pre-defined format to present the reader with a coherent page.

It interacts with users in a variety of ways including by reading cookies recognizing users' previous history, session variables, server side variables etc., or by using direct interaction (form elements, mouseovers, etc.).

A site can display the current state of a dialogue between users, monitor a changing situation, or provide information in some way personalized to the requirements of the individual user.
Some countries, for example the U.K. have introduced legislation regarding web accessibility

"Software systems"
There are a wide range of software systems, such as Java Server Pages (JSP), the PHP and Perl programming languages, Active Server Pages (ASP), YUMA and ColdFusion (CFM) that are available to generate dynamic Web systems and dynamic sites. Sites may also include content that is retrieved from one or more databases or by using XML-based technologies such as RSS.

Static content may also be dynamically generated either periodically, or if certain conditions for regeneration occur (cached) in order to avoid the performance loss of initiating the dynamic engine on a per-user or per-connection basis.

Plugins are available to expand the features and abilities of Web browsers, which use them to show active content, such as Flash, Shockwave or applets written in Java.

Dynamic HTML also provides for user interactivity and realtime element updating within Web pages (i.e., pages don't have to be loaded or reloaded to effect any changes), mainly using the DOM and JavaScript, support which is built-in to most modern Web browsers.

Turning a website into an income source is a common practice for web-developers and website owners.

There are several methods for creating a website business which fall into two broad categories, as defined below:

1. Content based sitesSome websites derive revenue by selling advertising space on the site (see contextual ads).
2. Product or service based sites
   

Some websites derive revenue by offering products or services. In the case of e-commerce websites, the products or services may be purchased at the website itself, by entering credit card or other payment information into a payment form on the site.

While most business websites serve as a shop window for existing brick and mortar businesses, it is increasingly the case that some websites are businesses in their own right; that is, the products they offer are only available for purchase on the web.

Websites occasionally derive income from a combination of these two practices. For example, a website such as an online auctions website may charge the users of its auction service to list an auction, but also display third-party advertisements on the site, from which it derives further income.


Source: en.wikipedia.org

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