To build around a certain target in a particular field of social activities in the form of universal significance, relatively stable and formal social institutions and norm to control the mass media, which includes the political and legal system, economic system, ideological and cultural system,etc.
Media specifications include:
1.internal media controls.
2. media self-regulation.
3 communication policy and communication rules.
4 journalistic ethics.
5 principles of objectivity and balanced principle.
6. The factors of gatekeepers.