the use of function overloading is to save the memory space,consistency and readabiliy.

Overloading: providing multiple behaviour to same object with respect to attributes of object.

see in programming, every thing is object. u r program also an object, function is also an object.

by using function overloading, we can  call specific behaviour of that according to what attributes we set at  compiled time.

mean we don't need to write different function name for different action.

For eg: Say a method called addUs(a,b) adds a and b.
So the definition will be

int addUs(int a, int b){

 return a+b;

}

But now if you want your arguments to be Objects of a class say
class Demo{
int height;
int width;
}
You want the same function addUs() to return a new object which would have attributes height and width having values as sum of the height & width of the 2 arguments passed.

So now the definition would be:

Demo addUs(Demo a, Demo b){
 this.height = a.height + b.height;
 this.widht = a.widht + b.width;
 return this;
}