A product family is a cluster of products that are built on the same platform. By designing multiple products with the same platform, a company saves on product development costs and can buy raw materials and components in larger quantities, thereby reducing its costs. A product family is usually marketed in the same way and sold through the same distribution channels. By doing so, a company can create a brand around the entire group of products, so that customers can feel comfortable with any product in the group. Customers are then more likely to upgrade to other products within the family, rather than buying from a competitor where the look and feel is different.
The product family concept works especially well when the product quality and customer service levels are high, so that customers have no reason to look elsewhere when they want to replace a product.