by a class, though in the symbolic notation (see below) the setuid bit is set in the triad for the user, the setgid bit is set in the triad for the group and the sticky bit is set in the triad for others. The set user ID, setuid, or SUID mode. When a file with setuid is executed, the resulting process will assume the effective user ID given to the owner class. This enables users to be treated temporarily as root (or another user). The set group ID, setgid, or SGID permission. When a file with setgid is executed, the resulting process will assume the group ID given to the group class. When setgid is applied to a directory, new files and directories created under that directory will inherit their group from that directory. (Default behaviour is to use the primary group of the effective user when setting the group of new files and directories, except on BSD-derived systems which behave as though the setgid bit is always set on all directories (see Setuid).) The sticky mode (also known as the Text mode). The classical behaviour of the sticky bit on executable files has been to encourage the kernel to retain the resulting process image in memory beyond termination; however, such use of the sticky bit is now restricted to only a minority of unix-like operating systems (HP-UX and UnixWare). On a directory, the sticky permission prevents users from renaming, moving or deleting contained files owned by users other than themselves, even if they have write permission to the directory. Only the directory owner and superuser are exempt from this. These additional modes are also referred to as setuid bit, setgid bit, and sticky bit, due to the fact that they each occupy only one bit. Notation of traditional Unix permissions Symbolic notation Unix permissions are represented either in symbolic notation or in octal notation. The most common form, as used by the command ls -l, is symbolic notation. The first character of the ls display indicates the file type and is not related to permissions. The remaining nine characters are in three sets, each representing a class of permissions as three characters. The first set represents the user class. The second set represents the group class. The third set represents the others class. Each of the three characters represent the read, write, and execute permissions: r if reading is