Native development kit (NDK) is a set of tools that allow Android developers to write code for their apps in languages like C and C++. These tools allow you to write code that runs directly on an Android device. The NDK is like a box of Lego blocks - you can use the pieces to build your own Android app that works exactly the way you want it to. By using the NDK, you can write faster and more efficient code than what you could do with just the standard Java components.