The optional referendum is a referendum which comes from a request by governmental authorities or the public. The best known types of optional referendums is the popular initiative to request a law, and the popular (or abrogative) referendum to repeal a law. The collection of signatures from the public is normally necessary to organize an optional referendum, but some jurisdictions allow government agencies to request for a referendum also. It is a form of direct democracy. The optional referendum is in contrast to a mandatory referendum in that it is a requested referendum, whereas the subject matter of a mandatory referendum is a legally required to be put to a referendum. There are a few major types of optional referendums: Authorities plebiscite: A referendum that is voluntarily placed on the ballot by a governmental authority (usually a legislature) Initiative referendum: A citizen-led effort to suggest and vote on a proposed law. Popular referendum: A citizen-led effort to oppose or repeal a law. Recall referendum: A citizen-led effort to remove an elected official before the end of their term of office. Depending on the area and position, a recall may be for a specific individual, such as an individual legislator, or more general such as an entire legislature. Politics of Switzerland and Voting in Switzerland In Switzerland the popular referendum is known as a facultative referendum (fakultatives Referendum; référendum facultatif, referendum facoltativo, referendum facultativ) It allows citizens to oppose laws voted by the federal parliament, cantonal and/or municipal decrees by legislative and/or executive bodies. It also allows them to propose new laws in a popular initiative. The popular referendum was first introduced in the cantons (e.g. in the Canton of Zurich since 1869). At federal level, the optional referendum was introduced by the Federal Constitution of 1874 (Article 74). The ratification of the Gotthard Treaty of 1909 triggered widespread protests and ultimately led to a petition being submitted.