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CHAPTER 2. HTML

The CSS language can be used to specify four kinds of properties: fonts, colors,

borders, and text spacing.

To simplify the presentation of HTML and CSS in this text, we will only

use the CSS method for specifying style and will ignore all other methods (e.g.

style based attributes of HTML tags). This allows us to ignore many HTML

tags (e.g. the ones that change the font type or font color) and many HTML

attributes. Indeed, Figure 2.1 show the 28 tags that we will consider and also

shows their main attributes.

The tags are divided into groups that we consider one at a time. We have

already seen the first four tags.

2.4

Hyperlinks

The hyperlink element has the form:

 CONTENTS 

The CONTENTS is typically some text or an image. The WEBADDRESS is a

URL that specifies the location of some web content online. The most commonly

used URLs are

  names of files on the server,e.g. report.html or doc/manual.html

  addresses of other pages on the web, e.g. http://www.whitehouse.gov

  mailto URLs which allow the user to use the browser to send email to a

prespecified address, e.g. mailto:gwb@whitehouse.gov.

  a link to some other form of media, e.g. a movie or document home.mov

or whitepaper.pdf.

2.5

Images

The image element has the form:

This is one of the few tags that does not have a matching  close  tag. The only

required attribute is the src, but it is a good idea to include a description of the

image for the vision impaired in the alt attribute. This may even be mandatory

if you want the page to meet minimum Federal Accessibility Standards.

The width, height attributes are optional and they can be used to rescale

the size of your image. Giving only the width will cause the height to scale

proportionately. Giving height and width may result in a picture that looks

stretched or flattened.