Can you describe what the Reign of Terror is?

The Reign of Terror was a period of violence during the French Revolution. It lasted from September, 1793 to July 1794 and is named for the many executions of those denounced as "enemies of the state", mainly in Paris but also in other areas of France. Most were guillotined (beheaded), as were King Louis XVI and his wife, Marie Antoinette, earlier in 1793.