setuid short for set user ID upon execution is Unix access

rights flag that allow users to run an executable with the

permissions of the executable's owner. This is often used to

allow users on a computer system to run programs with

temporarily elevated privileges in order to perform a

specific task. While the assumed user id privileges provided

are not always elevated, at a minimum that is specific.

setuid and setgid are needed for tasks that require higher

privileges than those which a common user has, such as

changing his or her login password. Some of the tasks that

require elevated privileges may not immediately be obvious,

though — such as the ping command, which must send and

listen for control packets on a network interface.