Held Wednesday, January 26, 2000
Overview
Today, we begin to consider how computers might represent documents by
visiting HTML, the hypertext markup language used on the World Wide Web.
We also consider general issues of hypertext.
Question 3 for today's class: Describe the appearance and purpose of five parts of the course front door.
Question 4 to answer for tomorrow's class: Do you prefer logical or physical markup? Why?
Notes
- There seems to be some confusion about the questions.
- The ``today's question'' is the question we discuss (directly or indirectly)
in today's class.
- The ``next question'' is the question we discuss in the next class.
- The number of a question corresponds to the number of the class.
- There seem to be some questions about the Risks digest
- No, we don't have a reliable news feed
- You subscribe by sending a letter to
risks-request@csl.sri.com
with one line: SUBSCRIBE.
- As an alternative, you can just check the ``latest risks'' Web page with
some regularity
http://www.csl.sri.com/~risko/risks.txt
- As another alternative, I can simply forward the digest when it arrives
- Assignments:
- Scan the HTML lab for Friday's class.
- Don't forget to send a response to question 4:
Do you prefer logical or physical markup? Why?
Contents
Summary
- About markup languages
- Physical vs. logical markup
- Some background on HTML
- HTML
- Handouts:
- We say that the World Wide Web is a form of hypertext.
- But What is hypertext?
- Sorry, while I have answers, I want to hear yours first.
- And How old is the concept of hypertext?
- One of the core problems we face in using computers is how to
represent information so that the computer can use and
understand it.
- At the most basic level, computers just ``know'' about two
values: 0 and 1.
- Fortunately, some other smart folks have figured out how to convince
computers to represent letters of the alphabet and such.
- Given that the computer already understands letters, we might just
decide to use those letters to describe the various parts
of hypertexts.
- We might also represent hypertexts using the 0's and 1's.
- Who should be able to read the document? Just a computer, or also
humans?
- What kinds of things should we include in the document?
- What do you have to represent? Basically, everything.
- Content
- Characteristics of various pieces
- Perhaps general document characteristics
- Links
- ...
- We say that languages for representing documents ``mark up''
the content of the document to indicate these characteristics.
Logical vs. Physical Markup
- In considering markup, there are two general ``philosophies'' for what
you mark: logical markup and physical markup.
- In logical markup, you indicate the role of
each piece of text. For example, you might indicate that
- This is a paragraph
- This is an important word or phrase
- This is a quotation
- This is the title of a book
- This is a top-level section heading in a paper
- In physical markup, you indicate the appearance
of each piece of text. For example, you might indicate that
- This should appear in Times Bold 12pt
- This should appear in a box 2 inches each side that is placed 3/4 inch
from the top margin and 5 inches from the right margin
- Why would you prefer one over the other?
Saturday, 22 January 2000
- Created as a blank outline.
Wednesday, 26 January 2000
Friday, 28 January 2000
- Removed the sections on HTML, which were not really covered.
(Moved to the next outline.)
Back to Lab: Getting Started in the MathLAN.
On to Lab: HTML.