What is affiliation?
Almost in every businesses we find some dealers or wholesaler who sale the products of different companies getting a fixed commission (%) from each sales. Such as: Samsung doesn't sell their products directly. It assigns dealers in different countries who sale the products offering them a fixed commission on their sales.
Affiliation is the online version of wholesale or dealership where a person does this business through his website. To be an affiliate you need to have a website of your own that will hold advertisement of different products of the companies. If anyone buys any product referring your site, you will get the commission from the company. You will not get less than 15% commission from any sales. Some site give up to 75% commission.
Now, I will introduce you with some sites that offer affiliate program: