Riot police are police who are organized, deployed, trained or equipped to confront crowds, protests or riots.

A protest is a public expression of objection, disapproval, or dissent towards an idea or action, typically a political one. Protests can be thought of as acts of cooperation in which numerous people cooperate by attending, and share the potential costs and risks of doing so. Protests can take many different forms, from individual statements to mass political demonstrations. Protesters may organize a protest as a way of publicly making their opinions heard in an attempt to influence public opinion or government policy, or they may undertake direct action in an attempt to enact desired changes themselves. When protests are part of a systematic and peaceful nonviolent campaign to achieve a particular objective, and involve the use of pressure as well as persuasion, they go beyond mere protest and may be better described as civil resistance or nonviolent resistance.