its about www and http presentation

1. Presented by:
Anil Pokhrel
BscCSIT 5th
sem
College of Applied Business
1

2. 2
Contents

WWW

Introduction

Structure

Components

Advantages and disadvantages

HTTP

Features

Architecture

Conclusion

3. 3

4. 4
Introduction
• The World Wide Web is a way of
exchanging information between
computers on the Internet.
• The World Wide Web is the
network of pages of images,
texts and sounds on the Internet
which can be viewed using
browser software .

5. 5
STRUCTURE
 Clients use browser application to
send URIs via HTTP to servers
requesting a Web page
 Web pages constructed using
HTML (or other markup language)
and consist of text, graphics,
sounds plus embedded files

6. 6

Servers (or caches) respond with requested Web page Or with error
message

Client’s browser renders Web page returned by server

Page is written using Hyper Text Markup Language (HTML)

Displaying text, graphics and sound in browser

Writing data as well

The entire system runs over standard networking protocols (TCP/IP,
DNS,...)

7. 7
Internet vs World wide web
• The Internet is a global system of
interconnected computer
networks.
• Its access is provided by
ISPs.
• It runs applications like
www, ftp, html etc
• Web is collection of text
documents and other resources,
linked by hyperlinks and URLs
• Usually accessed by web
browsers
• Its an application running on
Internet

8. 8
WWW COMPONENTS
Structural Components:
Clients/browsers – to dominant implementations
Servers – run on sophisticated hardware
Caches – many interesting implementations
Internet – the global infrastructure which facilitates data transfer

9. 9
Semantic Components:
Hyper Text Transfer Protocol (HTTP)
Hyper Text Markup Language (HTML)
extensible Markup Language (XML)
Uniform Resource Identifiers (URIs)

10. 10
The Fundamental concept

The Hypertext concept
Hypertext is text which contains links to other texts. The term was coined by Ted
Nelson around 1965.

The Hypermedia concept
Hypermedia is a term used for hypertext which is not constrained to be text: it
can include graphics, video and sound.

11. 11
Continue…..
WEB Browser
• A web browser displays a web document and enables users to access web
documents.
WEB Server
• This is a program that waits patiently for the browser to request a web page.
The servers looks for the requested information, retrieves it and send it to the
browser or sends an error message if the file is not found.

12. 12
Uniform Resource Locator (URL)
• These are the web addresses. The resource locator is an
addressing system .

13. 13
Advantages and Disadvantages
• Mainly free information
• Low cost of initial connection
• Rapid interactive communication
• Facilitates the exchange of huge
volumes of data
• Accesible from anywhere
• Has become the global media
• Danger of overload and excess
information
• Difficult to filter and prioritize
information
• No guarantee of finding
what one is looking for
• No regulation
• No quality control over
available data

14. 14

15. 15

The Hypertext Transfer Protocol (HTTP) is an application-level protocol for
distributed, collaborative, hypermedia information systems.

This is the foundation for data communication for the World Wide Web (i.e. internet)
since 1990.

Basically, HTTP is a TCP/IP based communication protocol, that is used to deliver data
(HTML files, image files, query results, etc.) on the World Wide Web.

16. 16
Basic features
HTTP is connectionless
HTTP is media independent
HTTP is stateless

17. 17
Basic architecture
The HTTP protocol is a request/response protocol based on the client/server based
architecture where web browsers act like HTTP clients, and the Web server acts as a
server

18. 18
How http works ?
Client
The HTTP client sends a request to the server in the form of a request method, URI,
and protocol version, containing request modifiers, client information, and possible
body content over a TCP/IP connection .
Server
The HTTP server responds with a status line, including the message's protocol version
and a success or error code, containing server information, and possible entity-body
content.

19. 19
Request method
GET : The GET method is used to retrieve information from the given server using a given URI.
Requests using GET should only retrieve data and should have no other effect on the data.
HEAD : Same as GET, but it transfers the status line and the header section only.
POST : A POST request is used to send data to the server, for example, customer information, file
upload, etc. using HTML forms.
PUT : Replaces all the current representations of the target resource with the uploaded content.

20. 20
DELETE : Removes all the current representations of the target resource given by URI.
CONNECT : Establishes a tunnel to the server identified by a given URI.
OPTIONS : Describe the communication options for the target resource.
TRACE : Performs a message loop back test along with the path to the target resource.

21. 21
1xx: Informational : It means the request has been received and the process is continuing.
100 continue : only a part of the request has been received by the server ,but as long as it has not
been rejected ,the client should continue .
2xx: Success : It means the action was successfully received, understood, and accepted.
201 created : the request is complete ,and a new resource is created
3xx: Redirection : It means further action must be taken in order to complete the request.
4xx: Client Error : It means the request contains incorrect syntax or cannot be fulfilled.
404 not found : the server can not find the requested page
5xx: Server Error : It means the server failed to fulfill an apparently valid request.

22. 22
Conclusion
1. HTTP is the protocol used to transfer data to and from the website.
2. WWW is the identifier that indicates that it is a web site and it uses the HTTP
protocol.
3. HTTP://anything.com, WWW.anything.com, HTTP://WWW.anything.com
leads to the same site.
4. Any prefix that is not reserved to a protocol can be used as a sub domain.

23. 23
References
http://www.differencebetween.net/technology/difference-between-http-and-www/
https://cscie12.dce.harvard.edu/lecture_notes/2007-08/20080130/slide13.html
https://www.tutorialspoint.com/http/http_overview.htm
https://www.tutorialspoint.com/http/http_status_codes.htm

24. 24