Retail markets and shops have a very ancient history, dating back to antiquity. Over the centuries, retail shops were transformed from little more than "rude booths" to the sophisticated shopping malls that we know today. Retailing involves the process of selling consumer goods or services to customers through multiple channels of distribution to earn a profit. Retailers satisfy demand identified through a supply chain. Some of the earliest retailers were itinerant peddlers. The term "retailer" is typically applied where a service provider fills the small orders of a large number of individuals, who are end-users, rather than large orders of a small number of wholesale, corporate or government clientele. Shopping generally refers to the act of buying products. Sometimes this is done to obtain final goods, including necessities such as food and clothing; sometimes it takes place as a recreational activity. Recreational shopping often involves window shopping (just looking, not buying) and browsing: it does not always result in a purchase.