Stoning is a traditional method of execution, used to punish prostitutes, adulterers, murderers and other criminals. Used since biblical times it has been criticized on the West and in the US as cruel and abandoned for more humane methods of execution, like electrocution, gas chambers and lethal injection.
However, the method is still popular in some countries. The criminal is wrapped into a sheet to ensure anonimity, and burried waist down into ground. The mob then applies rocks to the culprit. The stones should be of proper size so that a single stone cannot cause death. The culprit has a chance for salvation by running away. In the case the criminal manages to become free, then the punishment is often canceled. This option does not exist in any other method of execution.
The practice, and the customary associated absence of proper judicial process, is satirised in Monty Python's Life of Brian.