In fact, many programmers still do this today. And though it is not wrong to do so — unless you’re a
CSS zealot, all print-friendly pages should be excluded using either exclusion method, otherwise a
search engine will see two versions of those pages on your site.
Navigation Links and Breadcrumb Navigation
Friendly navigation is clearly desirable for any web site. Unfortunately, it sometimes creates duplicate
content. Take the example of a web site that inserts category IDs in URLs of products that are in multiple
categories in order to provide breadcrumb navigation. In this way the developer creates many different
URLs (one per category, actually) of substantially duplicate content. This section examines breadcrumb
navigation now in more detail.
Breadcrumbs are navigational aid elements, usually found on the top of a web page that look some-
home > products > fortune cookies
. They especially help users navigate when they
are deeply within a web site. In this case, using the back button is typically frustrating. And in the
case that a user arrives from a search engine results page, the back button also certainly doesn’t do
what you wish it would!
It’s worth noting that breadcrumb navigation is not the only problematic site navigation scheme around.
Matrix, faceted, and dynamic drill-down navigation systems are gaining rapidly in popularity. A consid-
erable number of large retailers, such as Wal-Mart, eToys, The Home Depot, and the Discovery Channel
Store implement these types of site navigation, and show where the industry is heading.
The duplicate content issues resulting from these complex systems are problematic as well, but this is
outside the scope of this book. The same general principles apply.
The SEO consequences of breadcrumb navigation are none when a site product is in only one category. The
category can be implied by the database, because there is a 1:1 relationship of product to category. There
fore, there is no need to pass the category ID in the URL — but even if it is present, there will be only one
permutation of product and category. Hence there is no duplicated content.
Rewriting the URLs does nothing to resolve this.
These three URLs are just as duplicated as
It’s just obscured in the former version.
Chapter 5: Duplicate Content
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