On a Linux system, a user account is a record that defines a user and their associated privileges and resources. A user account typically includes the following information:
A username: This is a unique identifier for the user account. It is used to log in to the system and identify the user.
A password: This is used to authenticate the user when they log in to the system.
A user ID (UID): This is a unique numerical identifier for the user account. It is used by the system to identify the user and their associated resources.
A group ID (GID): This is the numerical identifier for the user's primary group. It is used to determine the user's access to resources.
A home directory: This is the default directory where the user's files and settings are stored. It is usually located in the /home directory and has the same name as the username.
A default shell: This is the command-line interface (CLI) that the user will use to interact with the system. Common shells include bash, csh, and zsh.
In addition to these core elements, a user account may also include additional information such as the user's full name, email address, and other user-specific settings.
To create a new user account on a Linux system, you can use the useradd command or a similar utility. To modify an existing user account, you can use the usermod command or a similar utility. To delete a user account, you can use the userdel command or a similar utility.