You’ll have a special link, known as an affiliate link, for every product that you’re promoting. Affiliate links have tracking in them to make sure that you get credited with every sale you make. When someone clicks your affiliate link, then the merchant knows it was you who sent the customer.
Let me stress that affiliate links don’t affect the customer at all… they don’t pay more, they don’t miss out on anything, and they will most likely never know that they purchased through an affiliate link.
All it means is that when a customer buys something within a certain time period after clicking on your affiliate link, you get the commission.
So the big goal of affiliate marketing is to get as many people as possible clicking on your links and visiting merchant pages the more people that click on your affiliate links, the more chances you have of a sale occurring and earning a commission.