Web Engineering we define Web Engineering as follows: 1) Web Engineering is the application of systematic and proven approaches (concepts, methods, techniques,

Course Title: web Engineering Chapter No: 01

“introduction to web Engineering”

Course Instructor:ILTAF MEHDI

IT Lecturer, MIHE, Kart-i Parwan branch, Kabul

Web Engineering

we define Web Engineering as follows:1) Web Engineering is the application of systematic

and proven approaches (concepts, methods, techniques, tools) to cost-effective requirements analysis, design, implementation, testing, operation, and maintenance of high-quality Web applications.

2) Web Engineering is also the scientific discipline concerned with the study of theseapproaches.

Web Engineering

• The growth of the Internet and the World Wide Web has already had a significant impact on business, commerce, industry, banking and finance, education, government and entertainment sectors, and our personal and working life.

• Many birthright information and database systems are being migrated to the Internet and the Web environments.

• it provides an information representation that supports interlinking of all kinds of content, easy access for end users, and easy content creation using widely available tools.

Web Service• A web service is an application that is run by a

web server and that results in a series of URLs that will return their data in a format that is intended to be parsed by a 'generic' computer program instead of by a browser.

• The term "Web Services" is also used to refer to the SOAP/XML standard, that is a standard way to encode the information in Web Service charm.

Web Service

• Web Services can convert your application into a Web-application, which can publish its function or message to the rest of the world.

• Web Services are published, found, and used through the Web.

SOAP

• SOAP stands for Simple Object Access Protocol• SOAP is an XML-based protocol to let

applications exchange information over HTTP.• more simple: SOAP is a protocol for accessing

a Web Service.• SOAP is a communication protocol• SOAP is a format for sending messages

Web Application

• A web application is any application that uses a web browser as a client.

• The application can be as simple as a message board or a guest sign-in book on a website, or as complex as a word processor or a spreadsheet.

Web Application

• Web applications commonly use a combination of server-side script (ASP, PHP, etc) and client-side script (HTML, JavaScript, etc.) to develop the application.

• The client-side script deals with the presentation of the information while the server-side script deals with all the hard stuff like storing and retrieving the information.

WWW• WWW Stands for "World Wide Web." • It is important to know that this is not a synonym

for the Internet. • The World Wide Web, or just "the Web," as

people call it, is the Collection of internet resources, hyperlinked text, audio, and video files that can be accessed and searched by browsers based on standards such as HTTP and TCP/IP.

• The Web consists of pages that can be accessed using a Web browser.

Components of World Wide Web

• There are essentially three components which together form the World Wide Web;

They are:1) Internet, 2) Information Servers3) Web Browser4) Web Page5) Website6) URL

1. Internet

• The Internet, sometimes called simply "the Net," is a worldwide system of computer networks - a network of networks in which users at any one computer can, if they have permission, get information from any other computer (and sometimes talk directly to users at other computers).

• Internet is a public, cooperative, and self-sustaining facility accessible to hundreds of millions of people worldwide.

2. Information Servers • Information servers run on computers

connected to the Internet all over the world.• Information servers are processes (executing

computer software) which dish out information as requested from users connected to the same network/the public Internet.

• The most common information types of servers on the Internet today are:

a) Web serversb) FTP Servers

a. Web servers• Web servers are computers that deliver (serves up) Web

pages. • Every Web server has an IP address and possibly a domain

name. • For example, if you enter the URL

http://www.pcwebopedia.com/index.html in your browser, this sends a request to the Web server whose domain name is pcwebopedia.com. The server then fetches the page named index.html and sends it to your browser.

• Any computer can be turned into a Web server by installing server software and connecting the machine to the Internet.

b. FTP Servers

• FTP, or File Transport Protocol Servers; whose only function is to allow FTP clients to copy files of any kind (programs, images, text, etc.) between the client and server machines.

• FTP allows you to enter commands and filenames to send to, receive from, and otherwise manage files and directories on a remote computer.

3. Browser• The third component of the World Wide Web, a

new generation of Internet information called Web Browsers.

• Web Browser is a software application used to locate, retrieve and also display content on the World Wide Web, including Web pages, images, video and other files.

• The browser is the client run on a computer that contacts the Web server and requests information.

• The Web server sends the information back to the Web browser which displays the results on the computer or other Internet-enabled device that supports a browser.

3. Browser

The most popular browsers are: • Microsoft Internet Explorer• Firefox • Google Chrome• Apple Safari• Opera

4. Web Page• A web page or webpage is a document or

information resource that is suitable for the World Wide Web and can be accessed through a web browser and displayed on a monitor or mobile device.

• This information is usually in HTML or XHTML format, and may provide navigation to other web pages via hypertext links.

• Web pages frequently include other resources such as style sheets, scripts and images into their final presentation.

5. Website• A website, also written as Web site, web site,

or simply site, is a set of related web pages containing content (media) such as text, image, video, audio, etc.

• A website is hosted on at least one web server, accessible via a network such as the Internet or a private local area network through an Internet address known as a Uniform Resource Locator (URL).

All publicly accessible websites collectively constitute the World Wide Web.

Kinds of Web site

• Electronic commerce (e-commerce) sites• Blog (web log)• Celebrity websites• Community sites• Corporate websites• Dating websites• Forum websites

•Gallery Websites•Gaming websites•News sites•Personal websites•Religious sites•Search engine sites•Social networking sites

6. URL• Abbreviation of Uniform Resource Locator

(URL) it is the global address of documents and other resources on the World Wide Web.

• The first part of the address is called a protocol identifier and it indicates what protocol to use, and the second part is called a resource name and it specifies the IP address or the domain name where the resource is located.

URL

• The protocol identifier and the resource name are separated by a colon and two forward slashes.

• For Example:

a. ftp://www.pcwebopedia.com/stuff.exe

b. http://www.pcwebopedia.com/index.html

• The term "Web address" is a synonym for a URL that uses the HTTP / HTTPS protocol.