Affiliate advertising is a type of performance-based marketing in which an affiliate receives a commission for promoting a product or service. The affiliate, typically a website owner or blogger, will promote the product or service by placing links on their site that direct visitors to the merchant's website. When a visitor clicks on one of these links and makes a purchase, the affiliate earns a commission based on the amount of the sale. This type of advertising is beneficial for both merchants and affiliates as it allows businesses to reach new customers while providing an additional revenue stream for content creators.