User (computing) - User Account

User Account

A user's account allows a user to authenticate to system services and be granted authorization to access them; however, authentication does not imply authorization. To log into an account, a user is typically required to authenticate oneself with a password or other credentials for the purposes of accounting, security, logging, and resource management.

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, through a process known as identity correlation. In Unix systems, the username is correlated with a user identifier or user id.

Computer systems are divided into two groups based on what kind of users they have:

• Single-user systems do not have a concept of several user accounts.
• Multi-user systems have such a concept, and require users to identify themselves before using the system.

User accounts on multi-user systems typically include a home directory, in which to store files pertaining exclusively to that user's activities, which is protected from access by other users (though a system administrator may have access). User accounts often contain a public user profile, which contains basic information provided by the account's owner.

In online communities, screen names can become a mark of persona, some of them acquiring a certain level of fame from the contributions of their holders. Some famous screen names :

• CmdrTaco, of Rob Malda, founder of the website Slashdot.
• lcamtuf, of Michał Zalewski, a security expert.