alloc, new, copy indicate an object with a retain count of 1 and the responsibility is up to you to release it later. Same when you retain it, of course.
Else it indicates an object that is autoreleased and you don’t have to care.

A method always expects autoreleased objects as parameters and therefore doesn’t need to care about them.

That’s all!

If you add it to an array the object get’s retained. But it’s the array’s responsibility to release it later and you don’t have to worry.