Introduction

web-application development

Ever since the world has been introduced to the World Wide Web, it has amazed the users with its versatility, efficiency and availability. World Wide Web became a primary medium for information sharing, communication and evolved as a backbone for business across the world. It had been in existence for over 24 years now. World Wide Web closely relies on computer networks and primarily uses hypertext to transfer and present data to the users. An important aspect of World Wide Web is Web Application Development. Web Application development can be done if you understand the core technologies working behind the Internet. In the following tutorials you will understand that how WebPages are designed and coded using HTML and PHP.

What is a Web Application?

A Web application is a web based collection of html pages, classes, database, servlets and other resources. A Web Application can be defined as a dynamic and interactive web site developed with the help of server side programming. Web application development primarily means server side programming since it requests data stored with server. It is a method to implement user interaction, database connectivity and presenting the results to browsers in form of hypertext documents.

Online Movie Tickets, Online Banking, Social Networking, eCommerce Applications, Interactive Games, Online tutorials, Opinion  Polls all are examples of Web Applications. The latest entry is the CMS systems that allow a user to create websites with no knowledge of HTML.

Hypertext

Hypertext is a system that allows non-sequential, or non-linear linking of data. By creating documents in Hypertext you can create a collection of web pages that a user can read by following different paths offered through the links in these pages. The core idea behind hypertext is to have convenient information access and retrieval. Using Hypertext, linkages are created among different units of information so that a user does not have to follow a specific route through the content.

Hypertext is meant to link different kinds of information in the form of different media. It includes plain old text documents, data retrieved from a database, videos, images or audio files. A combination of these varieties of media can be included in one hypertext document.

You can create a digital library or an online shopping system by using the flexibility of creating interactive applications on the Internet.

Anchors and Links

Hypertext offers non-sequential connectivity between different documents or to different parts of same document by embedding links. These embedded links which are a path to another hypertext documents are called hyperlinks. When a user clicks on such a hyperlink using mouse or selects it by pressing enter key on the keyboard, she can jump to a different section of the same page, other page in the same collection of related documents, or altogether to another document.

The text or image that implements the hyperlink in a document is known as an anchor. It is usually a fragment of information that connects the current document to another. A link contains the reference of the other document

Difference between Anchor and a Link

Anchor Link
Anchor is the term that the user reads in a document to reach another section of page Link is the reference or a pointer that connects the anchor to another page or section of same document
An Anchor is visible clearly to the user as text, an image or a menu option How link is implemented may not be visible to the user. When a user rests the mouse cursor on an anchor the link is displayed on the status bar of the browser.
User interacts with an anchor in a hypertext document. The interaction is offered when a user places pointer of pointing device and a hand symbol  appears When the user clicks an anchor the browser opens the referenced document mentioned in the link of the anchor. It is an unambiguous reference that contains essentially two parts.
  • The location of the referenced document (local file system or a remote server location)
  • The communication protocol defining the access mechanism of the document.