1 / 36

CE80N Introduction to Networks & The Internet

CE80N Introduction to Networks & The Internet. Dr. Chane L. Fullmer UCSC Winter 2002. General Information. TA Office… Trailer #15 is no more TA offices moved to the ISB Rm 110.. same times as posted previously. Web Search based Essay. Essay based on Web search results

tavia
Télécharger la présentation

CE80N Introduction to Networks & The Internet

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CE80NIntroduction to Networks&The Internet Dr. Chane L. Fullmer UCSC Winter 2002

  2. General Information • TA Office… • Trailer #15 is no more • TA offices moved to the ISB • Rm 110.. same times as posted previously

  3. Web Search based Essay • Essay based on Web search results • 1-2 pages on any topic of interest • Must include results from at least four Web page references • References must be listed in a bibliography • Due Tuesday, February 26, 2002

  4. Class Information • Web page tutorial available on-line • Web page submission: • Email to venkat@cse.ucsc.edu • Subject: cmpe080n-assgn4 • Final Exam • Last class session • March 14, 2002

  5. Personal Web Page • No new pages received... • So, here’s mine :) • http://www.cse.ucsc.edu/~chane • My Home Page...

  6. Chapter 23

  7. Display Hardware Varies A variety of computers around the world are used to display web pages.

  8. A Browser Translates And Displays A Web Document A Web page is created to be used with any display hardware. The computer language provides general display guidelines without giving details.

  9. A Consequence of the Web Approach The same web page may appear differently. Using different browsers Using different computer hardware

  10. HTML Each web page is written in HyperText Markup Language (HTML). Has its own grammar rules Uses punctuation symbols in unusual ways Does not show spaces on displayed page uses free format input.

  11. Instructions In A Web Page Control The Output Tags are instructions that tell a browser how to display the page. Uses brackets < >to indicate a tag Uses tags in pairs (usually)

  12. A Web Page is Divided Into Two Main Sections The two main sections of a web page are: Heading <HEAD> </HEAD> Body <BODY> </BODY> Example Web Page

  13. Indentation Can Make HTML Readable Indentation makes it easier for people to read. Place tags on separate lines Indent items This is important when updating. Not done by the original creator as a rule Machine generated HTML can be ugly... i.e. HTML from M$ Word Machine Generated HTML

  14. HTML Text HTML uses tags to organize text into paragraphs. Tells the browser to end one paragraph and begin the next <P> Tells the browser to end the line and start a new line <br> Example Page

  15. A Web Page Can Link To Another Page Items that correspond to a link are anchored. Use tags: <A> </A> Use HREF to specify a link to a page: <A HREF=“http://www.site.com”> Link </A> Example Page

  16. HTML Allows Numbered And Unnumbered Lists HTML can be used to create a numbered (Ordered) list. Uses tags: <OL> </OL> For an unnumbered (Unordered) list. Use tags: <UL> </UL> Example Page

  17. Images must be converted into numbers stored in a file. Quantized and digitized.... Two methods of digitizing a picture are: To use a digital camera To use a scanner Images On A Web Page Are Digital

  18. Figure 23.8 Figure 23.8 Illustrations of (a) a digital scanner, and (b) a digital camera. Either produces a file stored on the computer’s disk.

  19. Digital Image Formats There are two popular forms of representing digital images. Including: Graphics Image Format (GIF) Joint Picture Encoding Group (JPEG)

  20. HTML Allows A Web Page To Include An Image Once an image has been stored on a hard disk, a web page can reference the file. Uses the tag: <IMG SRC=“xxx.gif”>

  21. Text Can Appear Adjacent To An Image An image on a web page can appear by itself or adjacent to text. HTML treats an image like an oversized “word” Example Page

  22. Images Can Be Aligned within Text HTML provides a way to control the details of how an image is aligned with surrounding text. Using the ALIGN tag ALIGN=TOP ALIGN=CENTER ALIGN=LEFT ALIGN=RIGHT Example Page

  23. More about Images • Image size may be controlled.. • Size • Height and Width (in pixels) • Borders can be added • Example Page -- No Control • Example Page -- Size Control • Example Page -- Borders

  24. Images Can Link To Another Web Page HTML uses the same pair of tags for text links as for image links. Use: <A HREF=“http://www.sample.com/index.html”> <IMG SRC=“yyy.jpeg”> </A> Example Page

  25. Some Browsers Can Stretch Or Shrink Images The IMG tag may include image height and width. Caveat: Not all browsers can resize images. It is best to store images in the desired size.

  26. The Background Can Be Controlled HTML allows one to specify the background of a Web page. Choose the color Specify the image Example Page

  27. Other Features Of HTML When a browser displays a table, it Aligns information into Rows Columns Multiple links may be associated with a single image.

  28. Importance of HTML Before HTML, displayed combinations of text and graphics required complex computer programs. Often was hardware specific CGA,EGA,VGA,SVGA, X,Mac...... Resolution of screens non-uniform

  29. GUI Tools Help With Web Page Creation Web authoring tools make it possible to compose a web page without learning HTML. Files are saved as HTML. Or *.htm for M$ systems

  30. HTML reference HTML The Definitive Guide Musciano & Kennedy, O’Reilly & Associates, Inc.

  31. Summary • HTML is the language of the Web. • HTML is hidden to the average user. • Browsers and servers handle the details and display the results • HTML is significant in that: • Sufficiently general to be widely used • Useable by people without computer programming knowledge

  32. Glossary • Homepage • A page of information accessible through the World Wide Web that is the main page for an individual or a company. • Hot List • The original term used for a list of bookmarks. Now essentially obsolete.

  33. Glossary • Hypermedia • An information storage system in which each page of information can contain embedded references to images, sounds, and other pages of information. • GUI • (Graphical User Interface) An interface that presents the user with pictures and icons rather than words.

  34. Glossary • Hypertext • A system for storing pages of textual information that each contain embedded references to other pages of information. • Mosaic • The first browser program for the World Wide Web.

  35. Glossary • Multimedia • A term describing any facility that can display text, graphics, images, and sounds. • Uniform Resource Locator • (URL) A short character string used by browsers to identify a particular page of information on the World Wide Web.

  36. Glossary • World Wide Web • (WWW) An Internet service that organizes information using hypermedia.

More Related