"A many-to-many-medium is one that allows large numbers of people to communicate effectively with large numbers of people. A one-to-many medium is something like a newspaper or television station, where a small number of people use an expensive technology to broadcast information to a large number of people. The reporters and editors and producers and owners of these media are gatekeepers, who determine which information the far larger audience sees, and which information it doesn't see. One-to-many media are usually centralized. To seize control of such a medium requires either a lot of money to buy air-time, or else a division of paratroopers to capture the broadcasting center."