It can be two things-
A link that points to an "in-between" website that then redirects you to the real website
A link that goes to the correct website but includes an affiliate tag in the url. For example, something like
The idea is that big retailers like Amazon pay people to link to their site (if the people clicking the link end up buying) so in this example, if you clicked on this link and bought 'someitem' then this Bob Dole guy would get a cut from Amazon for referring a customer to their site.
In other words.... any kind of link that you or someone else makes money off of based on how many clicks it gets.
Edited by devhen - 1/24/13 at 2:12pm