PolicyKit is an operating system component for controlling system-wide privileges in Unix-like operating systems. It provides an organized way for non-privileged processes to communicate with privileged ones. In contrast to systems such as sudo, it does not grant root permission to an entire process, but rather allows a finer level of control of centralized system policy. It is developed and maintained by David Zeuthen from Red Hat and hosted by the freedesktop.org project.
Fedora was the first distribution to include PolicyKit and it has since been used in various other distributions including Ubuntu since 8.04 and openSUSE since 10.3.
It is also possible to use PolicyKit to execute commands with elevated privileges using the command pkexec followed by the command intended to be executed with root permissions.