Okay kiddo, so you know how sometimes countries want to spy on each other to find out what they are doing? Well, sometimes they use special tools to help them do that. Those tools are called national technical means, or NTM for short.
NTM can be lots of different things, like satellites that can take pictures of the ground from really high up in space, or listening devices that can pick up conversations from far away. They help countries gather information about what other countries are doing, like where their soldiers are or what kind of weapons they have.
But you know what's really important, kiddo? Countries aren't supposed to use NTM to spy on everyday people, like you and me. They're only supposed to use them to gather information about other countries' military and government activities. So as long as everyone follows the rules, NTM can be really helpful for countries to learn more about each other and stay safe.