For whom is this particular product designed? That is the end-user or the potential customer.
End users in product development are people who ultimately use or intend to use the final product. It is often forgotten by designers that end users lack the technical skill and understanding that product designers possess, leading to features that yield low customer satisfaction. As far as information technology is concerned, end users are not customers in the usual sense. Instead, they are typically employees of the client. For instance, if a large retail corporation purchased the software, the end-users are the employees of the corporation who will use it at work, even if the company was the "customer" that bought the software.