The Guillotine is a method of execution that is usually quick. It consists of a wooden rack with a table at the back, a place for the victim's head with a slice at the top and a blade at the top. The victim is laid on the table with their hands usually tied behind them with their head through the hole, their head is secure and then the executioner pulls a rope sending the blade through the slice decapitating the victim and causing instant death. It was the main execution for members of the British royal family and aristocrats during the French Revolution
Fun fact - at one point, the Eiffel tower was planned to be a statue of a guillotine.