If you have ever read about the cold war or different missile tests done by different countries and have felt worried about the future, you should also know which countries have nuclear weapons.
Human history is filled with incidents where the introduction of specific weapons changed course of wars and international relations. Currently, nuclear weapons are those weapons. Capable of wiping out entire cities in an instant, these weapons of mass destruction are feared by all. And this fear has also meant that specific countries have put in a lot of effort to arm themselves with nuclear weapons to deter any possible invasion from other countries. Currently 9 countries are either known or suspected to own nuclear warheads. USA, in their steps of gaining military superiority over opponents, has stored many of their warheads in different other countries. But as those storage countries do not own those warheads and need detailed permission from USA to use them, those countries cannot be considered to own these devastating weapons.
The fear of mutually assured destruction (dropping nuclear bombs on each other and both getting annihilated) means that no one wishes to use these weapons. But this has not stopped them from stockpiling. North Korea is the only rogue state with nuclear capability who does not abide by any treaty regarding nuclear weapons. They also own the lowest number of warheads, but are capable of launching them from the land or the sea. Pakistan is limited to ground and air facilities whereas UK can only launch using their submarines. France can use its planes and submarines and a part of their stockpile is kept active as deterrence. Other countries like China, Russia and USA have access to the nuclear triad – meaning they can deliver nuclear warheads through ground, marine or aerial means.
If you want to read about the complete list of countries, take a look at Insider Monkey’s 9 Countries With Nukes: Does Turkey Have Nuclear Weapons? for their take on the topic.