William M. Pegram1 The Internet and the World Wide Web Chapter 7 – Computers: Understanding Technology

William M. Pegram2 Chapter Outline Uses of the Internet Connecting to the Internet Internet Addresses Packet transmission New applications

William M. Pegram3 Uses of the Internet Communications Entertainment E-Commerce Research/Knowledge Acquisition & Web Publishing Distance Learning

William M. Pegram4 Communications (electronic mail) –The most widely used Internet application –Usefulness of threatened by spamming, phishing, and worms Perhaps 80% of messages are spam (bulk unsolicited ) Phishing is that purports to be from someone but is from someone else and attempts to have the recipient reveal confidential information Worms are self-replicating programs and are used to get a computer to send spam –An internet service provider (ISP) is an organization that provides consumer access to the internet, usually charging a subscription fee, and ISP’s provide a unique address to their clients, e.g. where Comcast is the

William M. Pegram5 Communications (cont.) (cont.) –Most employers will provide a unique address to their employees (e.g. – addresses are also available for free from other sources – e.g. Yahoo, Hotmail, Gmail, MSN Such addresses can be permanent whereas those provided by ISP or employer typically end when one stops paying subscription to ISP or no longer works for the employer –Most providers permit one to access through specialized client programs, such as Outlook, Eudora, Outlook Express (succeeded by Windows Mail) and through a browser Student VCCS can only be accessed through a browser

William M. Pegram6 Communications (cont.) Chat rooms – real-time (live) discussions Instant messaging (IM) – like chat, but only two participants. Popular programs: –AOL Instant Messenger and ICQ –Yahoo! Messenger –Windows Live Messenger – previously MSN Messenger –IRC (Internet Relay Chat) Previously IM use has been social, but increasingly used in corporate world Mailing Lists – sent to an address goes to everyone on the list –Moderated – s have to be approved by administrator to go to everybody vs. unmoderated (no approval step) –One can opt to receive every or digests of s sent over a particular time period

William M. Pegram7 Communications (cont.) Web Sites for Communication –Blogs (originally called weblogs) – frequently updated journals posted on a web site – blogger.com provides blog creation for free –Electronic discussion groups/bulletin boards Moderated/unmoderated distinction here as well –Social networking sites – building online social networks Use a variety of techniques – chat, , discussion groups, blogging, etc. Users create a profile of themselves and can be friends with other users MySpace and Facebook are the most popular

William M. Pegram8 Entertainment Online Games – single and multiplayer Online Gambling Online Music and Video –mp3 is the most common format for sound –Music download services - iTunes –Increase in online video is one of the biggest recent changes in the Internet – sites where anyone can upload (youtube.com), TV network sites (watch TV shows)

William M. Pegram9 Electronic Commerce Business to Consumer – Apparel is biggest category, followed by books, music, video, auction items, toys, and computer hardware Business to business (B2B) – advertise products, order raw materials, recruit employees, file government forms and reports Advertising –Banner ads and popup windows –Targeted advertising – ads accompanying Google search engine results will be a function of the search keywords

William M. Pegram10 Research/Knowledge Acquisition Search engines Increase in plagiarism and plagiarism- detection tools (e.g. Wikipedia – online, collaborative encyclopedia

William M. Pegram11 Distance Learning WebCT and Blackboard are the two most popular platforms for college online courses; WebCT acquired by Blackboard in February 2006 and will be phased out as independent brand Both NVCC and GMU are increasing their use of distance learning

William M. Pegram12 Connecting to the Internet Types of Internet Connections –Dial-up –Cable –DSL –Wireless –Satellite

William M. Pegram13 Internet Addresses Internet Protocol (IP) Addresses – 4 numbers ranging from 0 to 255 separated by periods, e.g Each computer (network) connected to the internet has a unique IP address Type ipconfig at Command Prompt to determine IP address Some ISPs dynamically allocate IP addresses so they can change over time Uniform Resource Locator (URL) – e.g. – protocol then format then domain name then domain suffix then any path within

William M. Pegram14 Original Set of Domain Suffixes.com.edu.gov.mil.net.org 2-digit country codes, e.g..us (.us used by state and local governments, e.g. NVCC used to be nv.cc.va.us)

William M. Pegram15 New Domain Suffixes.aero - airline.biz.cat – Catalan language and culture.coop – business cooperatives.info.int.jobs.mobi.museum - museums.name.pro - professionals.tel.travel

William M. Pegram16 Packets Files sent over the internet are generally broken into smaller pieces, called packets. These packets are then reassembled at the other end The path a packet takes depends on availability – this is called packet-switching or dynamic routing

William M. Pegram17 Newer Internet Applications Peer-to-peer (P2P) file sharing - BitTorrent Internet telephone service (Voice over IP)