A referral link is a unique UR used by customers in referral programs to promote a company's brand and products. Customers enrol in a referral program, are given the referral link by the vendor, and then can use that link to drive traffic and sales to the vendor. The customer gets a cut of profit made from traffic to the link.
A reseller partner sells a vendor’s product directly to their client. In contrast to the relationship between affiliate/referral partners who are involved only at the start of the customer’s journey (it gets handed off to the vendor), a reseller partner owns the whole customer relationship.
Resellers are the most complicated partners to work with, and for good reason! They give you access to a relatively limited but highly qualified audience. This is why they often require more support and enablement resources.