Activism, in a general sense, can be described as involvement in action to bring about change, be it social, political, environmental, or other change. This action is in support of or opposition to one side of a controversial argument.
There are many different forms of activism; a select list follows.
... few viewers. Their response was to promote the channel through their ordinary channels BBC1 and BBC2, using terrestrial signals, and this is seen by some as influential ...