Summary

Summary

This hour explained how to create imagemapslinks that lead to more than one place, depending on where you click an imageas well as why and how to avoid using them in some circumstances. You saw how to define rectangular and circular link regions within an image, as well as irregularly shaped polygonal regions. You saw how imagemaps, although highly specialized in function, can nonetheless be very useful in some situations. When used selectively, imagemaps can be an important part of a web page's user interface.

Table 10.1 is a summary of the tags and attributes covered in this hour.

Table 10.1. HTML Tags and Attributes Covered in Hour 10

Tag/Attribute	Function
<img />	Inserts an image into the document.

Attributes
src="imageurl"	The image's URL.
alt="description"	A text description of the map image, intended to be used as an image replacement for situations where the image cannot be viewed.
title="description"	A text description of the area that may appear as a visual cue alongside the image.
usemap="name"	The name of an imagemap specification for client-side image mapping. Used with <map> and <area />.
<map>…</map>	A client-side imagemap, referenced by <img usemap="..." />. Includes one or more <area /> tags.
<area />	Defines a clickable link within a client-side imagemap.

Attributes
shape="value"	The shape of the clickable area. Valid options for this attribute are rect, poly, and circle.
coords="values"	The coordinates of the clickable region within an image; its meaning and setting vary according to the type of area.
href="linkurl"	The URL that should be loaded when the area is clicked.
alt="decription"	A text description of the area, intended to be used as an image replacement for situations in which the image cannot be viewed.