Description: A freehand drawing illustration showing a large number of users of a computer.A user is a person who utilizes a computer or network service. Users of computer systems and software products generally lack the technical expertise required to fully understand how they work. Power users use advanced features of programs, though they are not necessarily capable of computer programming and system administration. A Freehand drawing illustration showing a large group of users of computer network. A user often has a user account and is identified to the system by a username (or user name). Other terms for username include login name, screen-name (or screen name), account name, nickname (or nick) and handle, which is derived from the identical Citizen's Band radio term. Some software products provide services to other systems and have no direct end users.