End users are the ultimate human users (also referred to as operators) of a software product. The end user stands in contrast to users who support or maintain the product such as sysops, database administrators and computer technicians. The term is used to abstract and distinguish those who only use the software from the developers of the system, who enhance the software for end users. In user-centered design, it also distinguishes the software operator from the client who pays for its development and other stakeholders who may not directly use the software, but help establish its requirements.Rigsbee, Sarah, and William B. Fitzpatrick. "User-Centered Design: A Case Study on Its Application to the Tactical Tomahawk Weapons Control System. "Johns Hopkins APL Technical Digest 31.1 (2012): 76–82. This abstraction is primarily useful in designing the user interface, and refers to a relevant subset of characteristics that most expected users would have in common.
