Propaganda uses various techniques to shape perceptions and direct behavior. There are three main classes of propaganda: white propaganda from an openly identified source using gentle persuasion, black propaganda that is false and disguised, and grey propaganda without an identifiable source. Some common propaganda tools include ad hominem attacks, appealing to fear, bandwagoning to join the majority, using emotionally appealing but vague language, testimonials from respected figures, stereotyping groups, presenting only two choices as alternatives, and providing non-sequitur responses.