The phrase, "Affiliates are an extended sales force for your business", which is often used to explain affiliate marketing, is not completely accurate. The primary difference between the two is that affiliate marketers provide little if any influence on a possible prospect in the conversion process once that prospect is directed to the advertiser's website. The sales team of the advertiser, however, does have the control and influence up to the point where the prospect either a) signs the contract, or b) completes the purchase.
In corporate law and taxes, an affiliate is a company that is related to another company, usually by being in the position of a member or a subordinate role, a subsidiary. According to Investopedia, a subsidiary is a company "whose parent is a majority shareholder." (That means the parent owns 51 percent or more of the other company's shares of stock.