The document discusses Internet programming and related topics. It defines the Internet as a network of computers around the world that links different types of computers. It describes early networks like ARPANET and how the Internet became available for commercial use in 1989. Some key uses of the Internet include email, file transfers, discussion groups, and surfing the web. The World Wide Web consists of web pages with text, images, and hyperlinks that allow navigation between related pages organized into websites.

1. INTERNET PROGRAMMING
Neethu Narayanan
Assistant Professor
Department of Vocational Studies
St. Mary's College, Thrissur

2. INTERNET
 The INTERNET is a network of computers, which links many different
types of computers all over the world.
 ARPANET was the first WAN and had only four sites in 1969.
 In 1989, the U.S. government lifted restrictions on the use of INTERNET,
and allow its usage for commercial purposes as well.
 The popular term for the Internet is the “information highway”.
Internet Programming, Neethu Narayanan, St. Mary's College, Thrissur

3. The uses of the Internet
 Send e-mail messages.
 Send (upload) or receive (down load) files between computers.
 Participate in discussion groups, such as mailing lists and newsgroups.
 Surfing the web.
Internet Programming, Neethu Narayanan, St. Mary's College, Thrissur

4. What is Web?
 The Web (World Wide Web) consists of information organized into Web
pages containing text and graphic images.
 It contains hypertext links, or highlighted keywords and images that lead to
related information.
 A collection of linked Web pages that has a common theme or focus is
called a Web site.
 The main page that all of the pages on a particular Web site are organized
around and link back to is called the site’s home page.
Internet Programming, Neethu Narayanan, St. Mary's College, Thrissur

5. Internet Terminology
 Client
 Any computer on the network that requests services from
another computer on the network.
 Server
 Any computer that receives requests from client computers,
processes and sends the output.
 Web Page
 Any page that is hosted on the Internet.
 Web Development
 The process of creating, modifying web pages.
Internet Programming, Neethu Narayanan, St. Mary's College, Thrissur

6. Web Browser (Web Client)
 It is a program that retrieves information from the Web.
 Microsoft Internet Explorer
 Most commonly used browsers
 Netscape, Mosaic
 Many different computing platforms
 Opera
 The fastest browser on Earth
 Lynx
 Text based web client
Internet Programming, Neethu Narayanan, St. Mary's College, Thrissur

7. Web Server
 It is a program that waits for requests from the web browser.
 It provides four major functions
 Serving web pages
 Running gateway programs (CGI) and returning output
 Controlling access to the server
 Monitoring and logging all access
 E.g. Apache, IIS, Netscape Web server, …
Internet Programming, Neethu Narayanan, St. Mary's College, Thrissur

8. IP Addressing
 Domain Name Addressing
 Most web browsers do not use the IP address t locate Web sites and
individual pages.
 They use domain name addressing.
 A domain name is a unique name associated with a specific IP address by
a program that runs on an Internet host computer.
 This program, which coordinates the IP addresses and domain names for all
computers attached to it, is called DNS (Domain Name System )
software.
 The host computer that runs this software is called a domain name server.
Internet Programming,Neethu Narayanan, St.Mary's College, Thrissur

9. Structure of a Uniform Resource
Locators
http://www.chicagosymphony.org/civicconcerts/index.htm
protocol
Domain name
pathname
filename
http => Hypertext Transfer Protocol
Internet Programming, Neethu Narayanan, St. Mary's College, Thrissur

10. HTTP
• The transfer protocol is the set of rules that the computers use to move files
from one computer to another on the Internet.
• The most common transfer protocol used on the Internet is the Hypertext
Transfer Protocol (HTTP).
• Two other protocols that you can use on the Internet are the File Transfer
Protocol (FTP) and the Telnet Protocol
Internet Programming, Neethu Narayanan, St. Mary's College, Thrissur

11. Information on the Web
 A number of search tools have been developed and available to you on
certain Web sites that provide search services to help you find information.
Examples:
Yahoo  www.yahoo.com
Excite  www.excite.com
Lycos  www.lycos.com
AltaVista  www/alta-vista.com
MSN Web Search  www.search.msn.com
Internet Programming, Neethu Narayanan, St. Mary's College, Thrissur

12. HTTP
HTTP PROTOCOL
WEB SERVER
SERVER SIDE SCRIPT
DATABASE
WEB
CLIENT
Internet Programming, Neethu Narayanan, St. Mary's College, Thrissur

13. E-Mail - Electronic Mail
 Send mail electronically via the Internet
 Requires an account on a mail server and supporting software on
your PC
 The username and password will allow you to access your account
 All e-mail programs allow you to Send, Compose, Reply, and
Forward mail
Internet Programming,Neethu Narayanan, St.Mary's College, Thrissur

14. An E-mail Address
 Every e-mail address is unique and consists of two parts, a
user name and a host computer
 The @ sign is required
 The host computer can be omitted if you are logged onto the
same network or host computer
Internet Programming ,Neethu Narayanan, St. Mary's College, Thrissur

15. HTML
 Hyper Text Markup Language
 It is not a programming language.
 Cannot be used to describe computations.
 Use to describe the general form and layout of documents to be
displayed by the browser.
 Compose of “Content” and “Controls”
Internet Programming, Neethu Narayanan, St. Mary's College, Thrissur

16. Style sheets to add
presentation
Internet Programming, Neethu Narayanan, St. Mary's College, Thrissur
HTML Page

17. Client-Side and Server-side
Programming
 Client-side code
 JavaScript, JScript – Microsoft
 VBScript – Microsoft
 Embedded in <script> elements and execute in the browser, provides
immediate feedback to the user.
 Reduces the load on a server, reduces network traffic.
 Server-side code
 Execute on the server
 CGI/Perl, ASP, PHP, ColdFusion, JSP
 The code remains hidden from users, and browser independent.
Internet Programming, Neethu Narayanan, St. Mary's College, Thrissur

18. Web Programming
Language Model
Internet Programming, Neethu Narayanan, St. Mary's College, Thrissur

19. DHTML
 It is used to describe a set of animated web documents that built from
HTML, style sheets and scripts.
 There are three main parts of DHTML
 Positioning
 Style modifications
 Event handing
 It relies on the browser for the display and manipulation of the web pages.
Internet Programming,Neethu
Narayanan, St.Mary's College, Thrissur

20. Difference b/w Internet
and WWW
Internet Programming, Neethu Narayanan, St. Mary's College, Thrissur