The affiliate links are provided to you in several ways by the merchant and they are unique to your affiliate account.
There is usually a general link that covers the entire site, a link for every individual product, and links that apply specifically to banner ads.
No matter what though, WHATEVER your customer buys from the affiliate site, you get a commission from the sale.
So it doesn’t matter that I have a specific link above to the Fagus Wooden Jeep – if the customer clicks the link and ends up buying ANYTHING from that site, I still get the commission.
This is pretty cool, and particularly with programs like Amazon where people might just buy a fridge even though they got there through your link to a wooden toy!
Your affiliate link will place a cookie in your customers browser so that even if they don’t buy anything straight away, if they go back the next day or the next week and buy something from that site – you still get the commission.
The life cycle of these cookies varies from 24 hours to 30 days or longer, each program will tell you this when you join.