Non-local variable

A non-local variable is a variable that can be used by multiple sections of code, even if those sections of code are in different places. To give an example, say we have a piece of code to calculate how old someone is. This code uses a variable called "age" which stores the age of the person. If we want to use the same "age" variable in another part of code, even if this part of code is far away from the first part, we can use a non-local variable. This way, when we change the age in one place, it will be changed in the other place too.