Nonviolent action is an exercise of one’s abilities (falling short of using violence) to attempt to:
draw attention to a cause (usually some kind of injustice)
demonstrate by presence that the number of people opposing an idea is significant (think “million-man march”)
bring pressure to bear on people behaving in a way one finds problematic
directly fix issues
All sorts of things fall under nonviolent actions; from speaking to your neighbors to speaking at your kid’s school board meeting, speaking to your city council; getting people together to clean up some part of the city to to having a sit-in at the government offices, etc.
You’ll notice that, in many of those cases, using violence would not even make sense. But the idea is that your actions come not as a threat of some kind, but as a peaceful demonstration of your will, focused on a particular problem.
