Social movements are a type of group action. They are large informal groupings of individuals and/or organizations focused on specific political or social issues, in other words, on carrying out, resisting or undoing a social change.
Modern Western social movements became possible through education (the wider dissemination of literature), and increased mobility of labour due to the industrialisation and urbanisation of 19th century societies. It is sometimes argued that the freedom of expression, education and relative economic independence prevalent in the modern Western culture is responsible for the unprecedented number and scope of various contemporary social movements. However others point out that many of the major social movements of the last hundred years grew up, like the Mau Mau in Kenya, to oppose Western colonialism.
Political science and sociology have developed a variety of theories and empirical research on social movements. For example, some research in political science highlights the relation between popular movements and the formation of new political parties as well as discussing the function of social movements in relation to agenda setting and influence on politics.