Marketing channels are designed to connect consumers with a company's goods and services. The channels of distribution take the goods from manufacturing sites to retail sites, and the marketing varies with the distribution method. This is one reason why ads for cars are so different from ads for medicines.
A manufacturer uses marketing channels that are either direct or indirect. If a consumer goes to a barbershop, he pays directly for that service, instead of having to go through a middleman. However, if a consumer goes to a grocery store, the company that manufactured the soup that he orders uses the grocery store as its middleman, rather than operating its own outlets through which consumers make purchases. The more stops there are along the way between the manufacturer and the consumer, the higher the associated costs, as each entity has to make money from the transaction.
With some products, manufacturers only use specialized channels or even exclusive ones to bring their goods to the market. Some specialty clothiers only use high-end department stores or select boutiques to carry their line. This allows the fashion designer to target a very specific market with his clothes, as the people shopping in those stores are likely to have more income or more elegant sartorial tastes. This is why the clothing brands at a store such as Target are likely to be completely different from what a shopper finds in the boutiques on Rodeo Drive.