The term channel, in general, refers to the path that something takes to where it wants or needs to go. In marketing, the two channels that are matter are the distribution channels and advertising channels.
Distribution channels refer to the chain of intermediaries that a product or service needs to pass through for it to reach its target user or customer. This includes everything between the producer or manufacturer and the end customer. Resellers are part of the chain, including wholesalers and retailers.
In some cases, customers can buy directly from wholesalers. There are also some companies that sell their products directly in the own stores, in which case the chain is much shorter since customers can buy directly from the manufacturer. In most cases, though, companies use several distribution channels to cater to the different needs of different customers as well as adapt to geographical and logistical factors. Distribution channels can also be dictated by a company’s distribution strategy, in which they can opt for an intensive distribution, a selective one, or an exclusive one.
Advertising channels refer to the medium in which advertisements are disseminated. Advertising channels include TV and radio, print media (i.e. newspapers, magazine, and journals), online ads (i.e. emails, search engine and website ads), billboards, and point-of-purchase ads. Typically marketers use a mix of advertising channels to be able to reach their target market.