Affiliate Marketing is a marketing arrangement by which certain online retailers pay a commission to an external website for traffic or sales generated from its referrals. Referrals can be generated by people themselves, sending links or sharing them, sometimes unique codes are given.
A fairly common example is on YouTube, many creators have sponsors, who dedicate time to their videos to advertise a product from that sponsor.
For example, Bob’s YouTube channel is sponsored by a retailer, Bob’s viewers can buy products from this retailer for a reduced price often given in codes, like in this example, “10% off with code BOB10” This code is recognised by the retailer as sales generated by viewers of Bob, who in return receives a commission.