Intro to the Internet: Function & Structure

Internet and World Wide Web Overview

• The Internet and World Wide Web (www) facilitate communication, shopping, research, and finding places/directions
• The Internet is accessible from computers and cell phones at home, work, and school
• This session explains the origin and uses of the internet and basic terms associated with web pages and Uniform Resource Locators (URLs)

Session Goals and Objectives

• Explain the origin of the Internet
• Understand the major uses of the Internet
• Explain basic terminology associated with the World Wide Web
• Differentiate between the Internet and the World Wide Web
• Use a given search engine to search for information on the internet

What is the Internet?

• A global network connecting millions of computers
• A collection of vast information sources of interlinked computer networks
• Computer Network: A group of computers linked together over wired and wireless communications so information, resources, and ideas can be shared
• Local Area Network (LAN), Wide Area Network (WAN)

Internet: Nuts and Bolts

• It enables millions of connected computing devices
• Hosts = end systems
• Communication links use fiber, copper, radio, and satellite for transmission
• Packet switches forward packets (chunks of data) using routers and switches
• "Network of networks" featuring interconnected ISPs
• Protocols control the sending and receiving of messages and include TCP, IP, HTTP, and Skype
• Internet standards include RFC (Request for Comments) and IETF (Internet Engineering Task Force)
• Can be defined as a global system using the TCP/IP protocol, serving billions of users
• A network of millions of private, public, academic, business, and government networks of local to global scope linked by networking technologies

Internet: A Service View

• Infrastructure that provides services to applications like web, VoIP, email, e-commerce, and social nets
• Provides a programming interface to apps allowing the sending and receiving of programs to connect to the Internet
• Provides service options, like a postal service

Internet History

• Development began with electronic computers in the 1950s
• Born in 1969 out of the threat of war
• Four Universities linked together in the first wide area network; University of California at Los Angeles, University of California at Santa Barbara, University of Utah, and Stanford Research Institute
• The first message was sent over the ARPANET in 1969 from the computer science laboratory at University of California, Los Angeles to the second network at Stanford Research Institute (SRI)
• ARPAnet funding was through Advanced Research Project Agency Network
• ARPAnet was a cold-war era military project and a decentralized network of computers to coordinate military operations
• The network would enable scientists and researchers to share ideas and information quickly and easily; the idea that changed the world
• The NSF connected NSFnet to ARPANET in 1986 which became the Internet
• NSFNet terminated its network on the Internet in 1995 and became a research network
• Internet2 was founded in 1996
• there are over 550 million hosts connected to the Internet today

Ownership

• Organizations, corporations, governments, schools, private citizens, and service providers own pieces of the infrastructure
• Organizations oversee and standardize the Internet, as well as assign IP addresses and domain names
  • The National Science Foundation
  • The Internet Engineering Task Force
  • ICANN
  • InterNIC the Internet Architecture Board

Advantages of the Internet

• Sending/receiving emails
• Staying in touch with friends
• Shopping
• Downloading files, music, and films
• Access to interesting materials
• Meeting new people
• Finding housing and jobs quickly
• Serving as an easy and fast information source
• Streamlining work
• Enabling online shopping and bill payments from home
• Providing entertainment by saving time in queues

Disadvantages of the Internet

• Bullying, trolls, stalkers, and crime
• Addiction, time-wasting, and distractions
• Disconnect issues
• Identity theft, hacking, viruses, and cheating
• Spam and advertising
• Depression, loneliness, and social isolation
• Health issues and obesity
• Unnecessary purchases

World Wide Web (Web)

• Information organized into Web pages containing text and graphics
• Organization of files designed around a group of services on the Internet- Contains hypertext links/highlighted keywords and images that lead to related information
• Web site: Collection of linked Web pages with a common theme/focus
• Home page: The main/first page that all other pages on a website are often organized around

Web Resources

• Anything that can be acquired from the World Wide Web; websites, web pages, web services, email, and information from databases

Internet vs. World Wide Web

• The internet is not the same as the WWW
• The World Wide Web (WWW) is just one of the resources on the internet
• Other types of resources include voice over internet protocol (VoIP) such as skype
• To access the WWW the use needs a web browser

Internet Protocol (IP) Address

• A number that uniquely identifies each computer or device connected to the Internet

Domain Name

• The text version of an IP address
• It is often followed by a Top-Level Domain (TLD)

Internet Service Provider (ISP)

• A commercial organization with permanent connection to the Internet that sells temporary connections to subscribers
• Ex: Prodigy, America Online, Microsoft network, AT&T Networks

Accessing the Web

• An Internet connection is necessary, with special software called a browser to access the Web
• Web browsers are needed to connect to remote computers, open and transfer files, and display text and images
• Examples of Web browsers include:
  • Netscape Navigator (Navigator)
  • Internet Explorer

Hypertext Markup Language (HTML)

• Public files on web servers are ordinary text files that are formatted to be read by web browsers
• HTML is the standard language used on the web

Uniform Resource Locators (URL)

• Used to identify a Web page's exact location
• Multi-part addressing scheme that tells the Web browser:
  • Transfer protocol to use
  • Domain name of the computer
  • Pathname of the folder/directory on the computer
  • The filename

Structure of a URL

• Protocol (HyperText Transfer)
• Domain Name
• Filename

Terminologies of the Web

• Home page: The first page that a Web site displays
• Web pages: Offer links to other related Web pages which is known as surfing the web
• Downloading: The process of receiving information

The Web Browser

• A software application that allows users to access web pages and programs
• Can locate and display web pages, including text, graphics, audio, and video
• Sends requests to web servers
• Retrieves and manages website information

Generic Top-Level Domains

• .com Commercial organizations, businesses, and companies
• .org Non-profit organizations
• .net Network providers or commercial companies
• .edu Educational institutions
• .gov Government agencies
• .mil Military organizations

Finding Information on the Web

• Search tools provide search services

Functions of the World Wide Web

• Sharing Info; the web is a giant info library where information can be found
• Chatting and Connecting; where users contact friends
• Shopping Online; where users can order everything from clothes to gadgets
• Entertainment Galore; used for endless binge-watching and hilarious memes on platforms like Netflix, YouTube, and TikTok
• Learning Online; to take on classes and find answers to homework

Uses of the World Wide Web

• Website: Multiple web resources at web pages with with a particular theme that can be accessed from anywhere with a single domain name ex. www.infomogli.com , www.wikipedia.org
• Email: Electronic mail used to communicate with others by the message sent via the Internet ex. gmail.com , yahoo.com
• Online Study Materials: Find study material online for learning ex. Udemy, Khan Academy
• Web Services: A service offered by an electronic device to another electronic device.
• Downloadable Video: ex. YouTube , Max player, Netflix

Other Uses of the World Wide Web

• Online Music: Can download and listen to online mp3 files
• Ecommerce; Online shopping is a part of our life today ex. Amazon, Flipkart, Walmart
• News Sectors; news channels can be watched online
• Online Payment; Paying online is possible because of WWW and the Internet
• Online Banking; Almost every bank provides online banking to its customers for checking balance, transferring funds, and receving funds

Explore the Internet's primary functions, uses, and accessibility. Understand end systems, packet switches, communication links, and the role of RFC. Learn about Internet standards, bandwidth, protocols, and its overall structure.