index, and symbol. (The following explanation is adapted
from Hammerich and Harrison 2002, pp. 140–142.)
Icon An image is iconic if it bears a similarity or resemblance
to what we already know or conceive
about an object or person. Icons include paintings,
maps, and photographs and can range from very
realistic to very simplistic. On the Web, a common
icon is the house used to represent the home page,
as shown in Figure 3.
Index An image is an index if it is recognizable, not
because of any similarity to an object or person, but
because we understand the relationship between the
image and the concept that it stands for. A weathervane,
for example, has no resemblance to any aspect
of weather, yet it stands for the concept of
wind. A common Web index is the upward-pointing
arrow to indicate the top of a Web page as shown in
Figure 4. Indexical signs can be confusing and,
therefore, often require text to accompany them.
This is why the upward-pointing arrow on a scrollable
page is often also labeled, “Top of Page.”
Symbol An image is a symbol when it has no visual
or conceptual connection to an object or person. We
know the meaning of the image only because of
convention; that is, it’s something we’ve learned. A
word, for example, is a symbol because it does not
resemble what it stands for, nor does it have any
indexical relationship to what it signifies. Take the
word rose. It doesn’t look like a rose or bear any
relationship to the concept of a rose. A common
Web symbol is the line beneath a word or phrase
used to indicate a link, as shown in Figure 5.
Although indexical and symbolic images play important
roles in a Web site’s visual language, I will focus
primarily on icons in this paper because professional communicators
are likely to find that these images are the most
contentious during team discussions.