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The Internet and the World Wide Web
The Internet l l Millions of Computers all around the world No one person, company, or entity owns or controls the Internet.
The Internet’s Hardware l l Owned or Shared by thousands of private and public organizations Supercomputers called NAPs (Network Access Points), that serve as major hubs. NAPs are connect to each other and to Regional Routers through the largest lines of the Internet call “Backbones” Regional Routers are connect to Regional Networks
The Internet’s Hardware l Regional Networks connect to the various ISP. How do you connect to the internet from home?
Computers on the Internet l l l Request Data Provide Data Help Send Data Along the Network
Computers on the Internet l l Your personal computer at your house is an example of a computer that primarily requests data, called a Client. Computers that provide data are called Servers, since they “Serve” data to other computers. Computers that help information travel across the Internet are called Routers. Every time data takes a turn on the Internet, a Router is there to send it in the right direction.
Services on the Internet l l l Voice Over IP (Internet Protocol) Online Muli-Player Gaming Internet Relay Chat(IRC)
Services on the Internet l l l Peer to Peer File Sharing Video Conferencing Electronic Mail (e-mail)
Services on the Internet l l FTP (File Transfer Protocol) World Wide Web
How the WWW Works http: // - This is a “Protocol Prefix” that designates the file being requested as accessible via Hypertext Transfer Protocol. www - designates a requested file as World Wide Web document, originally needed to distinguish between Web files and other Internet files, this is often no longer needed. For example, you can go to edulaunch’s web site by typing http: //www. edulaunch. com or just http: // edulaunch. com edulaunch - Domain name that points to the server computer of the edulaunch web site. . com – Domain Name Extension designated for web sites with a commercial focus student_showcase - Directory or folder within which the web page being requested is located. bachelor_bet. html - This is the name of the exact file requested. You may be wondering: What is the purpose of slashes? They signify that you are moving deeper within the web site by entering a new folder or directory. For example, the bachelor_bet. html file is inside the student showcase directory.
How the WWW Works Domain Name Extensions The ending three-letter suffix of all top level domains are to designate what type of web site it is. Listed below are some of the most common domain extensions. . commercial use . education and resear ch . government al agenci es . military agenci es . networks or ISPs . org non-profit organi zation s Country Code Extensions There are now over 200 two-letter country code extensions. These designate a web site as originating from a certain country. For example, the web address of the London's famous metropolitan police - Scotland Yard is http: //www. met. police. uk Notice the two-letter country code at the end(. uk). A few examples of Country Code Extensions are listed below. . ar Argentina . il Israel . pr Puerto Ric o . br Brazil . in India . ru Russian Fed erat ion . cn China . it Italy . tw Taiwan . uk United Kin gdo m . us United Stat es Spain . kr South Kor ea . ie Ireland . mx Mexico
Searching the Web l Two Types of Web Searches l l Directories Search Engines
Search Engines l l Method of searching that uses software programs to search the web and record information. Programs Spiders § Robots § Crawlers § Intelligent Agents §
Search Engines l l l l All the Web Alta Vista Ask Jeeves Google Hot. Bot Lycos Wise Nut www. alltheweb. com www. altavista. com www. ask. com www. google. com www. hotbot. com www. lycos. com www. wisenut. com
How a Search Engine Works l Enter Your Request l l l (Called a Query) Request Compares it to the Search Engine (Database) Search Engine Delivers List based on relevancy.
How Google Works Information found on Google Inc.
Directories l Directory-based searches use people to search the web for similar web sites, they then place them in a directory. l Most Popular Directory-Based Search Engine www. yahoo. com
Directories l Directory-based searches use people to search the web for similar web sites, they then place them in a directory.
Getting the Whole Story? l Web searches only a cover around 20 -40% of the web. Much of the content on the web is hidden through password protected sites, firewalls, Flash™ sites, databases, and other things that search engines can’t read.
Boolean Searching l l l Most People Just Type What They are Looking For Best Way to Search the Web Allows the Search to be More Specific
Boolean Searching Boolean Operative What it Does Example and (+) Retrieves only pages that include all the keywords. Michael and Jordan, Michael + Jordan or Retrieves pages containing Texas or Austin any or all keywords. and not (-) Retrieves pages containing Michael an not Jordan, one keyword but not the Michael -Jordan other.
Boolean Searching Boolean Operative What it Does Example Phrase Searching Only retrieve documents where specified words appear in order, side by side. . "Remember the Alamo" Plurals If you want to search for only the plural of a word you must type in in plural. Concerts Capitals If you want to search for the capitalized version of the word you should type the whole word in CAPS. ROCKETS
Boolean Searching Boolean Operative What it Does Example Title Searching only for web page titles. +title: "Apostle Paul" Domain Searching for a specific web address within a domain +domain: . com Host Searching a host for a specific page. +host: www. ford. com
Boolean Searching Boolean Operative What it Does Example URL Searching web pages where the keyword appears in the URL or the web site address. +url: cars Link Searching Finding what web sites are link: www. ford. com linked to a specific site.
Web Searching Activities l Taken Over Common Research Tools l l Dictionary Thesaurus Replaced Trips to the Library for Professional Research The Web has become the new phone book.
Web Searching Activities You will complete two short Web search projects. First, you will use the Web to make a personal phone directory. The directory will contain the addresses and phone numbers of family and friends along with some helpful numbers from your local area. Second, you will use the Web to plan a trip. Included will be the route driven, the price and location of a rental car, the price and location of a hotel at your vacation destination and any stops or sights that will be taken in along the way.
Activity 1 – Making Your Own Phone Directory The internet has many natural advantages over the traditional phonebook. Some of those advantages are: l l Internet directories contain the most current listings available. Internet directories have access to all the nations telephone books. Internet directories do not need storage space in your home. Using internet directories you may search an entire state at once.
Activity 1 – Making Your Own Phone Directory In this activity you will construct your own personal directory. Included will be phone numbers and addresses of family members and friends, local schools, restaurants, car repair shops etc.
Activity 2 – Planning Your Vacation on the Web In this project you will use the internet to plan a fictitious car trip. Conditions for the trip include: l l l Your destination must be at least 600 miles from your school and no more than 1200 miles You will choose a hotel at your destination that costs less than $140 per night. You will find exact directions from your school to the hotel at your destination. You will find a mid-size car to rent with unlimited miles for at a cost of no more than $500. You will plan at least 2 activities at your destination and determine the cost of each. Your vacation will take place from June 1 st to June 6 th. You will need a six night hotel stay and a car rental for 6 days.
Activity 2 – Planning Your Vacation on the Web In this project you will use the internet to plan a fictitious car trip. Step One - Choose a Destination Step Two - Choose Lodging at Your Destination Step Three - Choose a Route Step Four - Reserve Your Rental Car Step Five - Plan Your Vacation Activities
Web Content Who’s Behind the Web Page? l Anyone can publish to the web l l No Laws to Monitor or Regulate its accuracy Always a Good Idea to Double-Check all information with a 2 nd Source. http: //www. britannica. com/
Web Security Internet security is a branch of computer security specifically related to the Internet. Its objective is to establish rules and measures to use against attacks over the Internet.  The Internet represents an insecure channel for exchanging information leading to a high risk of intrusion or fraud, such as phishing.  Different methods have been used to protect the transfer of data, including encryption.
Web Security Web Tracking l When a web site makes a record of your visit l “Cookie” – A small text file that helps with web tracking l Cookies enable the web site to determine how often you have: Visited Their Site § Date & Time of Your Last Visit § Specific Pages viewed on Site §
Web Security Web Tracking Example: l Amazon. com, you may have seen a message on the site that appears to be customized for you. “Hello, we thought you might be interested in these CDs”, then the CDs listed are all your favorites. l A cookie by itself is not a bad thing. In fact they can make surfing the web a richer experience and many well known sites will not function properly without them.
Web Security Advertising Spyware l Advertising spyware is software installed on a computer without the computer owner’s knowledge or permission.
Web Security Advertising Spyware l Uses Gathered Information to: l l l Download Advertisements (Pop-Up Banners) Identify Theft Computer Damage
Web Security Online Purchases & Encryption l Shop From a Secure PC l Shop Smart, and Only at Sites You Know & Trust l Shop with Your Credit Card l Consider Alternative Payment Methods l l One-time use Get a Handle on Spam
Web Security Online Purchases & Encryption l Encryption- Converts your text into gibberish l l File would need to be decrypt or translate it back to original format Majority of all reputable sites now offer encryption services. Look for the Lock Icon at the bottomw of the browser window. Encrypt your Own Files l Use PGP (Pretty Good Privacy)
Web Security Viruses l A program designed to replicate and spread to as many computers as possible. l l Immediately Visible Working unseen on your computer for months
Web Security Viruses l Email Attachments l l DO NOT OPEN ANY FILE ATTACHMENT UNTIL YOU HAVE CONFIREMD ITS ORIGIN Even From a Friend – Viruses will over take address books to spread itself.
Web Security Viruses l Trojan Horse l l Pretends to be something it is not, such as a product update or a free software download. Once you open it, the virus will begin to execute its programming. Keep Anti-Virus Software on your computer & up to date.
The Future of the WWW It will be almost impossible to predict what the Web will be like in the future. Ten years ago, few people would have predicted the rapid growth of the web in size and content. There are three things you can bet on. 1) More and more people will use the web. Not only is the world’s population increasing, but computer prices keep falling. As the “computer generation” grows into adulthood, replacing the "baby-boom" generation in the work force, web use will increase. 2) The Web will get faster and faster. Not too long ago, you would have been happy to have a 28. 8 Kilobytes per/sec modem. Then 56 k modems came along. Now there is DSL and Cable offering speeds over 1000 k. Over 70% of high school students in suburbia America already has a high speed connection. There is already talk about an Internet 2, bringing technology enabling everyone will have the speed that only today’s backbone lines enjoy. 3) The Web will grow continually grow more wireless. Popping up all over the United States are “hot spots”, areas where a business, school, or home is broadcasting their Internet connection. All laptops are now equipped with Mobile Technology to automatically connect to any wireless Internet signal it can find. Many restaurants are broadcasting a wireless signal in an effort to attract more customers. Many predict that within a few years, you may not need a wired connection at all.
The Internet and the World Wide Web