The word parity comes from the Latin paritas - equality. In a general sense, it means the equality of phenomena, the equal rights of groups. However, this term is used in politics and economics in slightly different meanings.
Gold parity - a fixed content of pure gold in a unit of national currency. Under the gold parity understand the ratio of currencies based on their gold content. The more gold a country’s currency contains, the more units of another currency it can be exchanged for. In the course also, the term "purchasing power parity" is the ratio of the purchasing power of currencies to a certain set of goods and services. This model can only function successfully with the free movement of capital, goods and services across borders. The higher customs duties, transportation costs and legislative restrictions on exports and imports, the less can be purchased for a certain amount of money. Accordingly, the more the exchange rate deviates from the established purchasing power parity. Currency parity - the ratio of two currencies established by law. It is assumed that at currency parity a balance is reached between supply and demand when exchanging one currency for another. It is established on the basis of the official content in the monetary unit of gold, or the conditional currency issued by the IMF - SDR (special drawing rights), or one of the world's hard currencies. Strategic parity is a state of international relations in which a victory is equally likely for all parties to the potential military conflict. This condition also implies that the stronger side is guaranteed unacceptably large losses in the event of a war. In modern conditions, in the event of a military conflict, third countries will inevitably suffer, therefore maintaining strategic parity is a common concern. Nuclear parity is the approximate equality of strategic nuclear forces. The situation when the confidence that the enemy is guaranteed to strike back keeps him from delivering a nuclear strike is called nuclear deterrence.
