Why should I use a pointer rather than the object itself?

Question

I'm coming from a Java background and have started working with objects in C++. But one thing that occurred to me is that people often use pointers to objects rather than the objects themselves, for example this declaration: Object *myObject = new Object; rather than: Object myObject; Or instead of using a function, let's say `testFunc()`, like this: myObject.testFunc(); we have to write: myObject->testFunc(); But I can't figure out why should we do it this way. I would assume it has to do with efficiency and speed since we get direct access to the memory address. Am I right?

Answer 1

Yes, you are correct.

passing a pointer to an object requires less memory on the call stack.

Passing a pointer to the object or data structure takes up less memory on the callback

than a pass by value, where a bitwise copy of the entire data structure or object must be made.

Suppose for example the data structure or class contains 255 bytes of data.

A bitwise copy of that argument on the call stack is 255 bytes rather than just

an 8 byte pointer, or whatever the size of the address pointer is... surely less