A rumour is a widespread report that is unproved in fact. It often serves to provoke, or to increase, antisocial collective behaviour. Rumour must be distinguished from lack of communication, for the rapid spread of rumour may very well be due to effective communication. The term rumour refers not to a method of its communication, but to its content. Under crowd onditions, it becomes difficult to check the source and accuracy of the information one receives, and thus to evaluate it, and so rumours are acted on as if they were true information. Rumour often arises because of a lack of information. People want to know what is happening, and so the rumour fills that need. Rumour may also be created as a rationalisation of or justification for emotional excesses and collective behaviour.
