Brand Owner:

Organization that own branded product (or service) in the marketplace

Retailer:

A retailer buys goods or products in large quantities from manufactureres or importers, either directly or through a wholeselar, and then sells smaller quantities to the end-user

Affiliate:

Affiliate marketing is a method of promoting web businesses (merchants/advertisers) in which an affiliate (publisher) is rewarded for every visitor, subscriber, customer, and/or sale provided through his/her efforts.