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Frames

There have been so many problems with frames since their inception that it bewilders us as to why any-

one would use them at all. Search engines have

a lot

of trouble spidering frames-based sites. A search

engine cannot index a frames page within the context of its other associated frames. Only individual

pages can be indexed. Even when individual pages are successfully indexed, because another frame is

often used in tandem for navigation, a user may be sent to a bewildering page that contains no naviga-

tion. There is a workaround for that issue (similar to the popup navigation solution), but it creates still

other problems. The

noframes

tag also attempts to address the problem, but it is an invisible on-page

factor and mercilessly abused by spammers. Any site that uses frames is at such a disadvantage that

we must simply recommend not using them at all.

Jacob Nielsen predicted these problems in 1996, and recommended not to use them at the same date.

Now, more than ten years later, there is still no reason to use them, and, unlike the also relatively

benign problems associated with tables, there is no easy fix. See

http://www.useit.com/alertbox/

9612.html

.

Using Forms

A search engine spider will never submit a form. This means that any content that is behind form navi-

gation will not be visible to a spider. There is simply no way to make a spider fill out a form; unless the

form were to consist of only pull-downs, radios, and checkboxes — where the domain is defined by per-

mutations of preset values, it could not know what combinations it submits regardless. This is not done

in practice, however.

There are some reports that Google, in particular, does index content behind very simple forms.

Forms that consist of one pull-down that directs the user to a particular web page are in this

category. However, as with the example of JavaScript links being spidered, we do not recommend

depending on this behavior. As a corollary, if such a form points to content that should be excluded,

it may be wise to exclude the content with an explicit exclusion mechanism, such as

robots.txt

or the robots

meta

tag!

There is no magic solution for this problem. However, there is a workaround. As long as your script

is configured to accept the parameters from a GET request, you can place the URLs of certain form

requests in a sitemap or elsewhere in a site.

So if a form submits its values and creates a dynamic URL like the following:

/search.php?category_id=1&color=red

that same link could be placed on a sitemap and a spider could follow it.

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Chapter 6: SE-Friendly HTML and JavaScript

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