The key terms include:
1. Product Class. At the most generic stage, this phrase refers to all products from all competing producers that serve the similar functional purposes in roughly the similar manner, despite short differences in appearance and performance; for example, all passenger cars manufactured in the world today are a product class.
2. Product Form. A lesser generic level, this term offers to all products within a group that are more same in customer perception and use than all items in a product class. Using the passenger car example, a product from within this product class would be luxury passenger cars.
3. Brand. Brand defines to various items in a product form produced by the similar organization or industries. Mercedes Benz is a brand within the product form of luxury automobiles.
4. Model. The least generic classification, this defines to a specific and individual item generated by an industries or an organization. A 300 E Class Sedan is a specific model produced under the brand of Mercedes Benz within the product form of luxury automobiles within the product class of passenger cars.