Most e-commerce websites contain mostly navigational pages (with little content) and product pages (with mostly duplicate content).
The challenge is easily (though not necessarily quickly) overcome, however, with a simple content strategy.
This article outlines five content techniques that I have used successfully on various e-commerce websites. Some of those techniques will be better suited than others to certain types of e-commerce websites. Accordingly, you might use just one or more of them on your own website, as appropriate.
1. Write Category Descriptions
For many e-commerce websites, optimization for primary keywords will focus on their category pages. The problem is that most category pages have little content, comprising mostly images and links.
An effective way to overcome that challenge is to write descriptions or introductory copy for each category, to be displayed above or below the product listings.
Zappos.com, for example, places a lengthy description (more like an article) at the bottom of category pages. Note how the descriptions include embedded links to other category pages.