When you're playing with toys or doing some activity, you can only reach certain things around you, but not everything at once. In the same way, when a computer program is running, it can only use certain parts of the program at a time. This area of the program that the computer can use is called the "scope".
Think of the scope as a little box that the program can work in. Just like you can only play with some toys in your room, the program can only work with certain parts of the scope. This little box has limits, which are called "boundaries" or "limits". These boundaries tell the program what it can and can't do inside the box.
For example, imagine that you're working on a drawing program. The scope for this program would be the area where you can draw and edit pictures. You wouldn't be able to move around things outside of that area, because it's beyond the scope.
In computer programming, the scope is used to keep things in place and make sure that the program is working on the right thing at the right time. It's a way for the program to stay organized and avoid mistakes.