User (computing)

A user is a person who uses a computer or network service. Users of computer systems typically have no experience on how the software works.
In order to identify oneself, a user has an account (a user account) and a username (also called a screen name, handle, nickname, or nick on some systems), and in most cases also a password.
A user account allows one to authenticate to system services. It also generally provides one with the opportunity to be authorized to access them. However, authentication does not automatically mean authorization. Once the user has logged on, the operating system will often use an identifier such as an integer to refer to them, rather than their username.