"Fun" fact: Those two things are connected! Without the repeal of the Fairness Doctrine by Reagan's FCC in 1987, the group called Citizens United would likely not have been able to form in 1988, as they would have been required to provide opposing viewpoints when they expressed their terrible views on national tv or radio networks.
Additional fun fact: Rush Limbaugh's nationally syndicated radio show (which began in 1988) also would not have been possible without the repeal of the fairness doctrine.
...but how do they work?