In product development, an end user (sometimes end-user) is a person who ultimately uses or is intended to ultimately use a product. The end user stands in contrast to users who support or maintain the product, such as sysops, system administrators, database administrators, Information technology (IT) experts, software professionals and computer technicians. End users typically do not possess the technical understanding or skill of the product designers, a fact easily overlooked and forgotten by designers: leading to features creating low customer satisfaction. In information technology, end users are not "customers" in the usual sense—they are typically employees of the customer. For example, if a large retail corporation buys a software package for its employees to use, even though the large retail corporation was the "customer" which purchased the software, the end users are the employees of the company, who will use the software at work. Certain American defense-related products and information require export approval from the United States Government under the ITAR and EAR. In order to obtain a license to export, the exporter must specify both the end user and the end use for undertaking an end-user certificate. In End-User License Agreements (EULAs), the end user is distinguished from the value-added reseller, who installs the software or the organization who purchases and manages the software. In the UK, there exist documents that accompany licenses for products named in the end user undertaking statements (EUU). End users are one of the three major factors contributing to the complexity of managing information systems. The end user's position has changed from a position in the 1950s (where end users did not interact with the mainframe; computer experts programmed and ran the mainframe) to one in the 2010s where the end user collaborates with and advises the management information system and Information Technology department about his or her needs regarding the system or product.