1. Chapter 22 - Browsing The World Wide Web Introduction Description Of Functionality –Obtain textual information, recorded sounds, or graphical images from a variety of sources on remote computers as requested. –Display the retrieved information automatically. –Store a copy of retrieved information on disk. –Print a copy of retrieved information on paper. –Follow a reference found in a document to related documents, possibly on different computers. Browsing vs. Information Retrieval –Although they transfer data efficiently, information retrieval services such as FTP do not display the contents of documents for users.

2. Chapter 22 - Browsing The World Wide Web –A browsing service permits users to view information from remote computers without knowing the names of files. After obtaining a copy of a document from a remote computer, the browsing service automatically displays the contents, and allows the user to select related documents. Early Browsing Services Used Menus[Gopher] –A menu-driven browsing system displays a menu of choices for a user. By selecting an item from the menu, the user can request the browsing service to retrieve information from a file or retrieve another menu.

3. Chapter 22 - Browsing The World Wide Web A Menu Item Can Point To Another Computer –A browsing system hides computer boundaries completely, and makes information on a a large set of computers appear to be part of a single, integrated system. A browser can jump from one computer to another without a user knowing or caring about which computers are being accessed. How a Browser Works An Example Point-and-Click Interface Combining Menu Items With Text

4. Chapter 22 - Browsing The World Wide Web The Importance of Integrated Menus – Curent browsing services embed menu items in other information, eliminating ambiguities and making it easier to understand each item, combining menu items with other information encourages a user to explore items as they are encountered. Menus Embedded In Text Are Called Hypertext –Although documents in a hypertext system can contain a complex maze of references, the complexity may not be obvious to a user who can view only one document at a time. Multimedia

5. Chapter 22 - Browsing The World Wide Web Video And Audio References Can Be Embedded In Text –A hypermedia system can embed references to nontextual information as well as references to textual information in a document. –If the user selects a reference to a document, the hypermedia system displays the document: if the user selects a nontextual reference, the hypermedia system plays the audio or displays the images. The World Wide Web –In addition to containing textual information, World Wide Web documents can contain sounds and graphical images. To display nontextual information, a computer must have multimedia hardware

6. Chapter 22 - Browsing The World Wide Web Browser Software Used To Access The Web –A Web browser consists of a program that provides access to hypermedia documents on the World Wide Web. A Web browser displays a given document, and allows the user to select among highlighted items, which can consist of either text, graphics, or sound. An Example Hypermedia Display Control Of The Browser External References Recording The Location Of Information –A Uniform Resource Locator consists of a short character string that identifies a particular multimedia document. Given a valid URL, a browser can go directly to the page without passing through other documents.

7. Chapter 22 - Browsing The World Wide Web Bookmarks How The World Wide Web Works A URL Tells A Browser Which Computer To Contact A URL Tells A Browser Which Server To Contact –Each URL uniquely identifies a page of information by giving the name of a remote computer, a server on that computer, and a specific page of information available from the server. Use Of The Name WWW In URLs A Browser Provides Access To Multiple Services

8. Chapter 22 - Browsing The World Wide Web Inside A Browser Program –A browser's novelty and power arise becasue it integrates access to multiple Internet services into a single, seamless browsing system. The browser uses information in the URL to automatically select an access mechanism from among such services as remote login, file transfer, and gopher. Getting Started With A Browser Summary An Observation About Hypermedia Browsing

9. Chapter 22 - Browsing The World Wide Web Terms – bookmark – browser – browsing – hypermedia – hypertext – information browsing service – menu – point-and-click interface – selectable item – Uniform Resource Locator (URL) – World Wide Web (WWW)