Some identify a market with a generic class of products. In relation to bargain holidays and / or package holidays, one hears of the beer market, the cake mix market, or the cigarette market. According to others, product markets refer to individuals who have purchased a given class of products. These two definitions of the market; the market as a class of closely related products versus the market as a class of people who purchase a certain kind of product view it from one of two perspectives: who are the buyers and what the products are.
In the first definition, buyers are implicitly assumed to be homogeneous in their behavior. The second definition suggests that the products and brands within a category are easily identified and interchangeable and that the problem is to search for market segments. In recent years, it has been considered inadequate to perceive market definition as simply a choice of products for chosen markets. Instead, the product may be considered a physical manifestation of a particular technology to a particular customer function for a particular customer group.