C++ - Difference between pointer of a class and object of class in initialization

Question

In C++ Suppose I have

class Sample{
 public:
 void someFunction();
};

In main() is there any difference between doing

Sample obj;
obj.someFunction();

AND

Sample *obj = new Sample();
obj->someFunction();

Is it only a matter of syntax or is there a performance/implementation difference? When should one be used over the other?

Answer 1

This is simple stuff - to do with heaps and stacks

Sample obj;
obj.someFunction();

obj is on the stack

AND

Sample *obj = new Sample();
obj->someFunction();

Is on the heap.

This needs to be deleted. It also lives outside scope.

The performance is about the same