The Anatomy of Revolution by Crane Brinton is a comparative study of the four great European revolutions: English, American, French, and Russian.
Crane's analysis is that the four revolutions followed a similar script.
Fall of the Old Regime The old regime is discredited, and probably running out of money. But there is hope, for that is what the revolutionaries are selling.
Rule of the Moderates and Dual Power Typically the old regime is succeeded by a regime of moderates, but the moderates soon find themselves in conflict with extremists who act illegally and independently of the moderate regime.
Reign of Terror The extremists win for a bunch of reasons, including that they are more ruthless and better organized. Then they embark on a campaign of terror and virtue, ruthlessly purging the world of injustice and sin and vice. Each of the four revolutions had its season of terror, including the Puritan revolution, the French Revolution with its Reign of Terror and Virtue, the Bolshevik Revolution with its Great Purge, and the Maoist Revolution with its Great Proletarian Cultural Revolution.
Thermidor Humans cannot live forever in a fervor of holy rage; eventually the tension breaks and people fall back into a more normal life. But the solution typically involves a dictator, nationalism, and foreign conquest.
One of the vital ingredients of a revolution is a rising class of people that are just feeling fit to be tied by the old regime, like the Puritans in Stuart England, the rebels in colonial British North America, and the philosophes in 18th century France.
In the Bolshevik Revolution, Terror was part of the plan. According to Gary Saul Morson,
An admirer of the French Jacobins, Lenin believed that state power had to be based on sheer terror, and so he also created the terrorist state.
But even the Leninist/Stalinist terror could not go on forever.
All revolutions offer a transformation of society into a new world of freedom and justice. But typically, after the fever of revolution cools off, society and the lives of its people is not much changed, except to have a more efficient and coherent government.