Mastering the Internet, XHTML, and JavaScript

1. Mastering the Internet, XHTML, and JavaScript Chapter 2 Web Browsers

2. Goals and Objectives Chapter Headlines Introduction Finding a web page Browser Tasks The two browsers Browser window structure Internet Explorer Netscape Communicator Opera Crazy Browser Managing web pages Browser Cache Plug-ins Bookmarks History list Customization Security Wireless browsing Summary Outline Chapter 2 - Web Browsers

3. 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 Chapter 2 - Web Browsers

4. 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 Chapter 2 - Web Browsers

5. 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 Chapter 2 - Web Browsers

6. 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 Chapter 2 - Web Browsers

7. 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 Chapter 2 - Web Browsers

8. 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 Chapter 2 - Web Browsers

9. Browser Tasks The following are important browser tasks: Viewing Navigating Downloading Printing E-mail tools Chapter 2 - Web Browsers

10. 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 Chapter 2 - Web Browsers

11. 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 Chapter 2 - Web Browsers

12. Browser Window Structure Chapter 2 - Web Browsers

13. Menus: File Edit View Favorites Tools Help Toolbars: Standard buttons Address bar (URL) Links toolbar Status bar Internet Explorer Chapter 2 - Web Browsers

14. Menus: File Edit View Go Communicator Help Toolbars: Navigation toolbar Address bar (URL) Personal toolbar Status bar Netscape Communicator Modules: • Navigator • Inbox • Newsgroups • Composer • Address book • Instant messenger Chapter 2 - Web Browsers

15. Netscape Communicator Chapter 2 - Web Browsers

16. Netscape Communicator Chapter 2 - Web Browsers

17. Menus: File Edit View Navigation Bookmarks Mail Window Help Toolbars: Main bar Navigation bar Address bar Personal toolbar Page bar Status bar Opera • Can be downloaded at http://www.opera.com • When it crashes it starts where it left off Chapter 2 - Web Browsers

18. Opera Chapter 2 - Web Browsers

19. Menus: File Edit View Favorites History Groups Options Tools Tabs Help Toolbars: Navigation bar Address bar Links bar Status bar Crazy Browser Chapter 2 - Web Browsers

20. 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 Chapter 2 - Web Browsers

21. 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 Chapter 2 - Web Browsers

22. 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 Chapter 2 - Web Browsers

23. 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 Chapter 2 - Web Browsers

24. 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 Chapter 2 - Web Browsers

25. 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 Chapter 2 - Web Browsers

26. 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 Chapter 2 - Web Browsers

27. 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 Chapter 2 - Web Browsers

28. Wireless Browsing Chapter 2 - Web Browsers

29. 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 Chapter 2 - Web Browsers