A procession is the formal march of a body of men. It is taken out on a political, religious, or festive occasion. A procession is an expression of public opinion.
It is brought out to demand the right from the ruling government or administrative authority. So people take part in it in an orderly way. A procession starts from a particular place. People walk in a line shouting slogans.
They also carry placards, festoons, banners, etc., which express their viewpoint. Sometimes, a procession may move along silently. There is generally much excitement, heat, and bustle in a political procession. The atmosphere becomes tense sometimes, and the police step in to maintain law and order.
When a procession moves along a street, all traffic stops. In a religious or festive procession, there is less heat and excitement but more solemnity than gaiety and mirth. But the common feature of almost all the processions is their bustle and noise.