The often clearly visible demonstrations are intended to spread awareness among the public, or disrupt the goings-on of the protested organisation. Sit-ins were a form of protest used to oppose segregation, and often provoked heckling and violence from those opposed to their message.
sit-ins were when colored people sat in a segregated are for white people which showed they were not willing to be segregated any longer.
boycotts were powerful because a large sum of people refused to use the things that segregated them and largely influenced busses and things like that.