Visual Basic.NET How to Program (PDF)

Appendix H Introduction to HyperText Markup Language 4: Part 1 1345
Marvin Cohen
Outline
H.1 Introduction
H.2 Markup Languages
H.3 Editing HTML
H.4 Common Elements
H.5 Headers
H.6 Linking
H.7 Images
H.8 Special Characters and More Line Breaks
H.9 Unordered Lists
H.10 Nested and Ordered Lists
H.11 Internet and World Wide Web Resources
Summary Terminology Self-Review Exercises Answers to Self-Review Exercises Exercises
H.1 Introduction
In this appendix we introduce the basics of creating Web pages in HTML. We write many
simple Web pages. In Appendix I, Introduction to HyperText Markup Language 4: Part 2,
we introduce more sophisticated HTML techniques, such as tables, which are particularly
useful for structuring information from databases. In this appendix, we do not present any
Visual Basic programming.
In this appendix, we introduce basic HTML elements and attributes. A key issue when
using HTML is the separation of the presentation of a document (i.e., how the document is
rendered on the screen by a browser) from the structure of that document. In this appendix
and in Appendix I, we discuss this issue in depth.
H.2 Markup Languages
HTML is a markup language. It is used to format text and information. This “marking up”
of information is different from the intent of traditional programming languages, which is
to perform actions in a designated order.
In HTML, text is marked up with elements, delineated by tags that are keywords contained
in pairs of angle brackets. For example, the HTML element itself, which indicates
that we are writing a Web page to be rendered by a browser, begins with the start tag
and terminates with the end tag . These elements format your page in
a specified way. Over the course of the next two appendices, we introduce many of the
commonly used tags and how to use them.
Good Programming Practice H.1
HTML tags are not case sensitive. However, keeping all the letters in one case improves program
readability. Although the choice of case is up to you, we recommend that you write all
of your code in lowercase. Writing in lowercase ensures greater compatibility with future
markup languages that are designed to be written with only lowercase tags and elements. H.1