username

n. unique name by which a user is identified when accessing a multi-user system (Computers)

User in a computing context refers to one who uses a computer system. Users may need to identify themselves for the purposes of accounting, security, logging and resource management. 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 (see below). Users employ the user interface to access systems, and the process of identification is often referred to as authentication.
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