INT20CN Computer Networks

Tutorial #6

1. Before coming to the tutorial, use your browser to "view source" for this tute sheet. Can you understand the HTML markups used? If you don't, ask for it to be explained in the tutorial

2. Show^[1] the <A> tag that is needed to make the string "ACM" be a hyperlink to http://www.acm.org.

3. In the Web materials for INT20CN, your lecturer (usually) prefers logical markups for text emphasis. The alternative is to use physical markups. Why do you think purists recommend the use of the logical markup?

4. In the lecture notes, mention was made of the philosophical difference between designing for the "structure" of a Web page, versus designing for its "appearance". Explain the difference between each of these, and comment briefly on their advantages and disadvantages.

5. In this lecture, we discussed the authoring of what we termed Web pages. You will also commonly hear people talk Home pages and Web sites.
   1. What is a Home Page, and how is it different to any other Web page?
   2. What is a Web site, and how is it different to a Web page?

6. Philosophical question: Why do I have to deal with this stuff? In general, most Web-page authors do not write HTML code "by hand" -- they either use a Web Authoring package such as DreamWeaver, MS FrontPage, Claris HomePage, etc, or alternatively they use the "Export as HTML" option in their favourite word processor. Give at least one reason why your lecturer regards it as useful for a student in this subject to have a rudimentary knowledge of HTML.

7. Research 1: In the lecture notes, the "hyperlink" example showed the value of the HREF as a full URL. At least two other variations exist for the value of the HREF. Discover what they are, and how to use them. Hint: they're all used in this tute...

8. Research 2: One interesting aspect of the Web is that the Netscape people have defined a de facto standard set of 216 "Web Colours" which their browser will render correctly. Other colours will (often) simply be mapped by Netscape browsers to the "closest" of the 216 available. Other browsers have adopted this set of colours as well.
   1. Why do you think Netscape specified 216 colours, when almost all modern computers have at least "8-bit" video, and can therefore display 256 colours?
   2. Find out how you specify "Netscape compatible" colours in the standard hexadecimal RGB format (where, eg, white is "#FFFFFF").
   3. How should this affect your choice of colours in Web backgrounds and images?

9. Research 3: The Web Accessibility Initiative is a project of the World Wide Web consortium. Find out what you can about this initiative, and its relevance to good design of Web pages.