THE INTERNET AND WORLD WIDE WEB: by Silvia Pereira Chapter 2
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THE INTERNET AND WORLD WIDE WEB: by Silvia Pereira Chapter 2
THE INTERNET AND WORLD WIDE WEB: Chapter 2 by Silvia Pereira History of the Internet Began as a networking project by the Pentagon – Goal was to build a network that: Allowed scientists from around the world to share information and work together Could work even if part of the network was destroyed by a disaster How the Internet Works Connecting to the Internet – Dial-up access – DSL and ISDN – The modem on the computer uses a telephone line to connect (slow speed) A higher speed connection using regular copper telephone wires Cable Modem Provides high-speed connection through a cable television network Access Providers These are businesses that give people and companies access to the Internet for a fee. – An ISP gives phone numbers which allow access – – Connects people to an access point (point of presence: POP) An OSP includes member-only features A WSP provides wireless access to users with wireless modems or Web-enabled mobile devices How Data Travels the Internet Connected computers work together to transfer data and information around the world – Use servers and clients Carriers of network traffic are known as the Internet backbone Data is transferred from one network to another until it reaches its final destination Internet Addresses An addressing system is needed to send data to a specific destination – – An IP address is a number that uniquely identifies each computer to the Internet A Domain name is the text version of an IP address Every domain name has a top-level domain, identifying the organization associated with the domain The World Wide Web Each document on the Web is called a Web page A Web site is a collection of related pages and items that are stored on a Web server A Web browser allows users to use pages A home page is the first page a Web site shows – Can be changed to whatever the user wants it to be Downloading is how a computer gets information Web Addresses Each Web page has a unique address, known as a URL A URL is typed into the Address text box at the top of the browser window – It consists of a protocol, domain name, and maybe a path to a specific page A Web server is a computer that sends requested pages to computers Navigating Web Pages Links – Connect from a Web page to another related page – – Nonlinear way to get information Use of links is referred to as “surfing the Web” Are usually underlined and in a color different from the other text on that page Searching for Info on the Web A search engine finds Web sites and pages about chosen topics – – Keywords are entered in the text box Hits, or Web page names that contain text with the keywords, are displayed A spider is a program that saves the list of keywords used A subject directory puts pages into a set of categories Types of Web Pages Portal News Informational Business/Marketing Educational Entertainment Advocacy Personal Caution! No one oversees the contents of these pages, so don’t assume they’re accurate. Multimedia on the Web An application that combines text with: – – – – – – Graphics Animation Audio Video Virtual reality Plug-Ins E-Commerce A business transaction occurring over the Web – B2C: sale of goods and services to the public – C2C: when one consumer sells directly to another – Electronic storefront Online auction B2B: when a business offers goods and services to another business Technical support E-Mail It’s the transmission of messages and files via a computer network – – E-mail program: used to conduct e-mails One must address to whom e-mail is being sent to – An address has a user name and a domain name A user name is unique to each user in a domain Address books are useful Contains a list of names and e-mail addresses FTP and Mailing Lists File Transfer Protocol – Permits file uploading and downloading Mailing Lists – Group of e-mail names and addresses under a single name Everyone on that list receives a copy of a message in their mailbox Can subscribe and unsubscribe Newsgroups and Message Boards Newsgroups: – – Online area where users have discussions about a particular subject through articles Members send messages so others can reply – – Thread: a discussion that’s made up of an original article and all subsequent replies A news server stores and distributes messages Message boards are similar to newsgroups, but they don’t need a newsreader to participate in discussion Chat Rooms and Instant Messaging Chat rooms – Place on the server that allows users to chat Chat: a real-time conversation – Real-time: people are conversing online at the same time; no time elapse Instant Messaging – Communication service that allows people to exchange message or files Also in real-time Netiquette Code of acceptable behaviors users should follow on the Internet – – – Avoid offensive language Avoid sending spam Don’t use all capital letters – Use emoticons to express emotion – It’s like SHOUTING! :) Use abbreviations and acronyms for phrases BRB means Be Right Back Web Publishing It’s the development and maintenance of Web pages Five major steps to Web publishing – – – – – Plan a Web site Analyze and design a Web site Create a Web site Deploy a Web site Maintain a Web site 5 Steps of Web Publishing Plan a Web site – – Identify the purpose of the site Determine ways to make the site unique Analyze and design a Web site – – Determine how to meet the aforementioned goals Design the layout – Text, graphics, audio, video, and virtual reality Decide if this is possible, or if it is taking on too much 5 Steps of Web Publishing cont’d Create a Web site – Compose the site Deploy a Web site – Store the site on a Web server Registering the site with search engines is a good way to ensure many people see it, for it will appear in the hit list for searches on related keywords Maintain a Web site – Frequently make sure information is updated and links are current