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Discovering Computers
Chapter 2The Internet and World
Wide Web
TED - ideas worth spreading
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Ch 4Processor
Control Unit
Arithmetic Logic Unit (ALU)
Arithmetic Logic Unit (ALU)
InputDevices
Ch 5
StorageDevices
Ch 7
OutputDevices
Ch 6
MemoryData
Information
InstructionsData
Information
InstructionsData
Information
Control Unit
Ch 1 – Introduction
Ch 2 – Internet & WWW
Ch 3 – Application Software
Ch 8 – System Software
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What is a network?A collection of connected computers
Backbone of the InternetInternet is the worldwide network that connects
businesses, governments, schools, and individuals
Providers
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Providers of InternetAn access provider is a business that provides access to the Internet (free
or for a fee)1. Internet Service Provider (ISP), Regional
or National2. Online Service Provider (OSP) (AOL, MSN,
for example)3. Wireless Internet Service Provider (WISP)
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IP (Internet Protocol) address
Domain name is the text versionof Internet protocol (IP) address
DNS server translates the domain name into IP address
Is a number that uniquely identifies each
computer connected to the Internet
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Broadband high-speed connection
Broadband high-speed connection
Slow-speed technology
Slow-speed technology
How do you connect to Internet?
Dial-up accessmodem in your computer uses a standard telephone line to connect to the Internet
Dial-up accessmodem in your computer uses a standard telephone line to connect to the Internet
Digital subscriber line (DSL)
Cable ISP
Wireless ISP
Cellular broadband
Power line communication
Satellite broadband
Digital subscriber line (DSL)
Cable ISP
Wireless ISP
Cellular broadband
Power line communication
Satellite broadband
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High-speed broadband Internet service
Cable Internet service DSL Fiber to the Premises (FTTP) Fixed wireless Cellular Radio Network Wi-Fi Satellite Internet Service
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What we do online?
Communicate Research Shop Bank Trade
Entertainment Download Music
Share Videos
Web Application
Functions of Internet
WWW
Message board and News group
Chat rooms and Instant messaging
VOIP (as Google Talk)
E-commerce
File transfer
Multimedia
Virtual reality
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What is the World Wide Web (WWW)?
Billions of documents, called Web pages, linked together on computers throughout the world
Web page
Contains text, graphics, sound, or video and links to other
Web pages
What is E-mail? Short for electronic mail
The transmission of messages and files via a computer network
The original service on the Internet
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Multimedia
An application that combines text with:
Graphics Animation Audio
Video Virtual Reality
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A graphic is a digital representation of nontext information
Graphic formats include BMP, GIF, JPEG, PNG, and TIFF
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A thumbnail is a small version of a larger graphic
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Animation is the appearance of motion created by displaying a series of still
images in sequence
Catching a mouse
What is streaming audio / video?
The process oftransferring audio/video
in a continuousand even flow
Enables you tolisten/view audio/video
as it downloadsto your computer
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Downloading vs. streaming
Soon the speed of wireless downloading will exceed the speed necessary for viewing a motion picture
At the same time wireless broadband will be everywhere
Then all line connections (telephone, DSL, cable) will become obsolete
Streaming on the move, paying for the content not for the delivery.
What is virtual reality (VR)?
Use of computers to simulate real or imagined environment
Appears as a three dimensional (3-D) space Used for games and many practical applications
Business to business (B2B)Business providing goods and
services to other businesses
Consumer to consumer (C2C)One consumer sells directly to another
What is E-commerce?
Business to consumer (B2C)Sale of goods to general public
Short for electronic commerce Business transaction that occurs over the Internet
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IM (instant messaging) A real-time service that notifies you when one or
more of your people are online and allows you to exchange messages or files
What is a chat room? Real-time typed conversation
that takes place on a computer Chat room is location on
server that permits users to discuss topics of interest
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VoIP (Voice over Internet)
enables users to speak to other users over the Internet
Also called Internet telephony
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Message BoardA message
board is a Web-based discussion group
Downloading /uploading Downloading is the process of a computer
receiving information Uploading is the process of a computer
sending information
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FTPFTP (File Transfer Protocol) is an Internet standard that
permits file uploading and downloading with other computers on the Internet
Many operating systems include FTP capabilities
An FTP server is a computer that allows users to upload and/or download files using FTP
E-mail The transmission of messages and files via a
computer network Messages can consist of simple text or can
contain attachments, such as documents, graphics, or audio/video clips
Internet access providers usually provide an e-mail program
What is an e-mail address? Unique name that consists of a user name and domain
name of user’s email server
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An e-mail program allows you to: Create Attach files to e-mail Send to a individual or a group Receive Forward Reply to e-mail Print Delete Move emails between email folders
Maintain your address bookScheduling
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A mailing list is a group of e-mail names and addresses given a single name
Subscribing adds your e-mail name and address Unsubscribing removes your name
To a message different types of files can be attached
Attached file can be read, viewed or listen to
An address book, a calendar, a scheduling book are supported by an email program.
Gmail provides Voice Over Internet (Gmail)
Some email programs include anti-spam features and other ways of filtering
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1. Using e-mail software, you create and send a message
2. Your software contacts software on your service provider
3. Your service provider determines best route for data and sends message, which travels along Internet routers to the recipient
4. When recipient uses e-mail software to check for e-mail messages, the message transfers from incoming mail server to recipient’s computer
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What is good with email?
Email is a natural service similar to post office. It explains its usefulness.
It’s ubiquitous.
It allows exchange of information between individuals and groups and does that well.
Email is free, open, protocols used to encode and transfer are not owned by anyone.
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Email is weak on collaboration
Email and its descendents (instant messaging, blogs) allow online discussions, but they are not well suited for that: you are easily lost in the deluge of messages.
Email allow some collaboration on documents but it is problematic: the deluge of different versions of attached documents is hard to reconcile.
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World Wide Web (WWW)Web pages, linked together throughout the world
Web page
Contains text, graphics, sound, or video and links to other Web pages
Web siteCollection of
related Web pages
Web browserProgram used to access
and view Web page
Search engineProgram used to select
Web pages according to a criteria and evaluate them
Tim Berners-Lee
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WWW was invented by Tim Berners-Lee in 1989. He was working at CERN, and wanted a way for physicists to share information about their research – the World Wide Web was his solution.
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The World Wide Web, or Web, consists of a worldwide collection of electronic documents (Web pages)
A Web site is a collection of related Web pages and associated items
A Web server is a computer that delivers requested Web pages to your computer
What is a URL?
Uniform Resource LocatorUnique address for a Web page
You can use your Web browser to access a Web page using a Uniform Resource Locator (URL)
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Web publishing is the development and maintenance of Web pages
Plan a Web site
Analyze and
design a Web site
Create a Web site
Deploy a Web site
Maintain a Web site
What is a Web browser?
InternetExplorer
NetscapeFirefox
Program that allows you to view Web pages and provides access to other functions of the Internet
Chrome Safari
Plug-ins Programs that
extend the capability of a browser
You can download many
plug-ins at nocost from variousWeb sites
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Tabbed browsing allows you to open and view multiple Web pages in a single Web browser window
How a Webpage travels the Internet?
What is a home page? The first page that a Web site displays Provides connections to other Web pages
What is a hyperlink (link)?
Item found elsewhere on same Web page
Different Web page at same Web site
Web page at a different Web site
A file on the same computer An email service
Built-in connection to another related Web page location
WWW in plain English
Advocacy Blog WikiSocial
NetworkContent Personal
Portal
What are the basic types of Web sites?
NewsInfor
mationBusiness/Marketing
Education
Entertainment
Podcast
What is a portal?
A Web site that offers a variety of services from one, convenient location
…, sports, e-mail, news, weather, auctions, online communities (Web sites that join people with similar interests)
MSN portal
What is a news Web site?
Contains newsworthy material Stories and articles relating to current events, life,
money, sports, and the weather
National Public Radio
What is an informational Web site?
Contains factual information Created by organizations and government agencies
Home improvement
What is a business/marketing Web site?
Contains content that promotes products or services Allows you to purchase products or services online
AT&T - Phone service, DIRECTV, Wireless, DSL Internet
What is an educational Web site?
Learn how airplanes fly or how to cook a meal Some colleges offer online classes and degrees
Technology Review
Offers avenues for formal and informal teachingand learning
What is an entertainment Web site?
Offers an interactive and engaging environment featuring music, video, sports, games, and more
YouTube
What is an advocacy Web site?
Contains content that describes a cause, opinion,or idea
SOLIDARITY, SUSTAINABILITY, AND NON-VIOLENCE
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Blog / Vlog uses a regularly updated journal format to
reflect the interests, opinions, and personalities of the author and sometimes
site visitors
How to Vlog? Click on the picture to learn
What is a Blog? Click on the picture
What are Wikies?
Collaborative Web site that allows users to create, add to, modify, or delete the Web site content via their Web browser
http://en.wikipedia.org/wiki/Main_Page
What is a content aggregator?
Business that gathers and organizes Web content and then distributes, or feeds, the content to subscribers for free or a fee
News aggregator
What is an online social network?
Encourages members to share their interests, ideas, stories, photos, music, and photos
Media sharing Web site
http://www.socialnetwork.com
What is a personal Web site?
Web page maintained by private individual or family Reasons: sharing life experience with the world
or job hunting
http://www.stallman.org
What is a podcast?
A website containing audio files that can be downloaded and played on the computer or MP3 players
http://www.pointofinquiry.com
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WWWInformation
presented on the Web must be evaluated for accuracy
No one oversees the content of Web pages
SearchFind Web sites and Web pages by entering
words or phrases called search text Also called a keywordAny Web site that is listed as the result of a
search is a hit
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Search engine
Finds information related to a
specific topic
Subject directory
Classifies Web pages in an
organized set of categories
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The history of Google’s search engine
In 1996 two PhD students Larry Page and Sergey Brin at Stanford University in California worked on a research project.
They believed that a search engine that analyzed the relationships between websites would produce better ranking of results than existing techniques, which ranked results according to the number of times the search term appeared on a page.
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The search engine
Convinced that the pages with the most links to them from other highly relevant web pages must be the most relevant pages associated with the search, Page and Brin developed their search engine.
The company was incorporated as Google Inc. in 1998 at a friend's garage.
Both Brin and Page had been against an "advertising funded search engines" model, and they wrote a research paper in 1998 on the topic while still students. However, they soon changed their minds.
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Google’s triumvirate: Eric E. Schmidt, Larry Page , Sergey Brin
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Intelligent search
Search engine: present vs. future
Question: key-words vs. understanding the question
Search: look for matches between documents and key words vs. use statistical analyses and computational linguistic to search through a huge documents base
Answer: sorted list of prospects vs. the precise answer
What is netiquette?
Golden Rule: Treat others as you would like them to treat you.
Code of acceptable behaviors users should follow while on the Internet
To see the online addition to the book click here
