Mastering the Internet, XHTML, and JavaScript

1
Mastering the Internet, XHTML, and JavaScript

• Chapter 2
• Web Browsers

2
Outline

• Crazy Browser
• Managing web pages
• Browser Cache
• Plug-ins
• Bookmarks
• History list
• Customization
• Security
• Wireless browsing
• Summary

• Goals and Objectives
• Chapter Headlines
• Introduction
• Finding a web page
• Browser Tasks
• The two browsers
• Browser window structure
• Internet Explorer
• Netscape Communicator
• Opera

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Goals and Objectives

• Goals
• Understand and master the use of web browsers,
  to make surfing the web a more pleasant and
  productive experience
• Objectives
• Browser Tasks
• Browser Window Structure
• Microsoft Internet Explorer
• Netscape Communicator
• Opera and Crazy Browser
• Managing browsers cache, plug-ins, and
  customization
• Managing surfing bookmarks, privacy, and
  security
• Browsers for hand-helds

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Chapter Headlines

• 2.1 Introduction
• You need a web browser to view web pages
• 2.2 Finding a web page
• The browser uses the URL of the web page to
  locate its web server computer
• 2.3 Browser Tasks
• Common browser tasks are viewing, navigation,
  downloading files, and printing
• 2.4 The Two Browsers
• Internet Explorer is widely used and Netscape is
  second
• 2.5 Browser Window Structure
• All browsers have title bar, menu bar, toolbars
  and status bar
• 2.6 Internet Explorer
• Fast and versatile browser but has no tabs,
  filters, or skins

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Chapter Headlines

• 2.7 Netscape Communicator
• Comes in two versions 4.8 and 7.01
• 2.8 Opera
• Claims to be the fastest browser on earth and has
  skins too
• 2.9 Crazy Browser
• Imitates IE, but is a tabbed browser, and has
  popup filters and killers
• 2.10 Managing Web Pages in a Browser
• Each page has URL, XHTML file, and content
  display
• 2.11 Browser Cache
• It speeds up downloading of web pages
• 2.12 Plug-ins
• It enables rendering of many different file types

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Chapter Headlines

• 2.13 Bookmarks
• It enables rendering of many different file types
• 2.14 History List
• Use browser history list to trace your past
  navigation experience
• 2.15 Customization
• Change browser colors, fonts, and other settings
  to suit your use and style
• 2.16 Security
• HTTPS, digital keys, and certificates protect
  data on internet
• 2.17 Wireless Browsing
• Ability to Sync handhelds for mobility

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Introduction

• A web browser is a computer program that displays
  web page content
• The user can specify the requested web page, by
  typing or clicking on a link, in a browser
• Browser can, then, locate and retrieve relevant
  web pages from servers
• Browser window is like the window of any other
  computer application

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Finding a Web-page

• Type the page URL
• Browser sends URL to DNS server which replies
  with IP address of requested server
• TCP/IP packets go to the server through routers
• Web server, upon receiving the packets, locates
  the file and sends it to your browser through
  routers

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Browser Tasks

• The following are important browser tasks
• Viewing
• Navigating
• Downloading
• Printing
• E-mail tools

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Two Browsers

• Internet Explorer (IE) and Netscape Communicator
  (NC) are two important browsers
• To download IE go to http//www.microsoft.com
• To download NC go to http//www.netscape.com

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Browser Window Structure

• A browser window has several bars on top of the
  window and one on the bottom of the window
• Title bar displays the title of current web
  page
• Menu bar contains the pull down menus
• Navigation bar to navigate through web-pages
• Address bar to type URL addresses
• Status bar displays messages about the
  progress of current tasks
• Display area displays the web page content

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Browser Window Structure
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Internet Explorer

• Menus
• File
• Edit
• View
• Favorites
• Tools
• Help

• Toolbars
• Standard buttons
• Address bar (URL)
• Links toolbar
• Status bar

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Netscape Communicator

• Menus
• File
• Edit
• View
• Go
• Communicator
• Help

• Toolbars
• Navigation toolbar
• Address bar (URL)
• Personal toolbar
• Status bar

• Modules
• Navigator
• Inbox
• Newsgroups
• Composer
• Address book
• Instant messenger

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Netscape Communicator
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Netscape Communicator
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Opera

• Can be downloaded at http//www.opera.com
• When it crashes it starts where it left off

• Menus
• File
• Edit
• View
• Navigation
• Bookmarks
• Mail
• Window
• Help

• Toolbars
• Main bar
• Navigation bar
• Address bar
• Personal toolbar
• Page bar
• Status bar

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Opera
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Crazy Browser

• Menus
• File
• Edit
• View
• Favorites
• History
• Groups
• Options
• Tools
• Tabs
• Help

• Toolbars
• Navigation bar
• Address bar
• Links bar
• Status bar

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Managing web pages

• Managing web pages deals with three aspects
• URL
• XHTML file
• Display in browser
• A user can save a web page URL by making it a
  favorite in IE or a bookmark in NC
• A user can print the web page he is viewing by
  using the Print button
• A user can save the web page by using Save As
  option from the File menu

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Browser Cache

• A browser cache speeds up the retrieval and
  display of web pages that are being re-visited
  during a session
• Browsers use two types of caching schemes
• Memory cache
• Disk cache
• Memory cache saves web pages during its current
  session
• Disk cache saves web pages from its previous
  session
• When a page is requested, the browser first
  checks its memory cache and then disk cache.
• Browser also checks for updates

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Plug-ins

• Plug-ins are programs that run within the browser
• Plug-ins appear to be a part of the browser even
  though they are separate programs
• The browser informs the user whenever a plug-in
  is needed for a web page
• They are easy to install
• Examples include
• Adobe Acrobat Reader to view .pdf files
• Macromedia Shockwave plays animation and sound
• Macromedia Flash to view animations
• Apple Quicktime plays text, animations, video,
  and sound

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Bookmarks

• A bookmark is a saved link to a web page
• User can name the bookmarked links
• E.g. my bank account, my home page
• Bookmarks in one browser/machine cannot be
  visible in another browser/machine
• Bookmark managing task include
• Adding
• Deleting
• Organizing
• IE refers to bookmarks as Favorites

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History List

• History allows users to retrace their surfing
  steps
• History can be
• Short term
• Long term
• Short tem history is related to Memory cache
• Long term history is related to Disk cache
• CRTL H keyboard shortcut usually displays
  browser history list
• Some browsers also have separate History button

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Customization

• Browsers are customizable by users to fit their
  specification and style
• The user can customize
• Default options
• Default web page
• Fonts
• Colors
• Toolbars
• Display of images
• Java and Javascript
• Style sheets
• Cookies options
• Configure mail and news groups server
• Change the size of cache

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Security

• Security is important to prevent unauthorized
  access to the information passed between clients
  and servers
• Security over the internet is ensured by using
  encryption and decryption techniques
• Encryption and decryption technology is
  implemented by using Secure Sockets Layer (SSL)
  developed by Netscape
• SSL is a communication protocol and uses the
  HTTPS protocol
• Encryption systems incorporate
• Public and Private Key
• Digital Certificate

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Wireless Browsing

• Wireless browsing is the browsing activity on
  miniature screens of small electronic devices
• Some examples of devices where wireless browsing
  is incorporated are
• Pocket PCs
• Hand-held PCs
• Cell phones
• PDAs
• Wireless browsing can be online or offline
• Offline wireless browsing is called sync for
  short, in which web pages are downloaded on the
  device for viewing them later
• Wireless browsing is different for reason such as
  screen size and disk space and have special
  browsers

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Wireless Browsing
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Summary

• A web browser provides access to a web page
• Browsers enable internet users to perform useful
  tasks
• Internet Explorer and Netscape Communicator are
  two major browsers
• A browser window has a generic structure
• Menus and Toolbars in any browser allow the user
  to change settings and perform browser tasks
• Browser cache speeds up the display of re-visited
  web pages
• Plug-ins run within the browser
• Browsers can be customized to suit the user style
• Security is a major issue with internet
  communications
• Wireless browsing is different from desktop
  browsing