When products are in price sets, they can be sold a special discounts depending on a customer group. Basicially, Price Sets are the relationship between Customer Groups and special pricing on a set of products. For example, your eCommerce Site might have gold, silver, or bronze pricing levels based on preferred customer membership.
You can create two kinds of Price Sets: Automatic and Manual.
You can see existing price sets by selecting Store Manager > Price Sets.
The Price Sets screen provides the following information: