What are pointers parameters in functions for?

[adn258]

So I know you can use this in examples like

void changeInt(int &i)
{
	i += 5;
}

and than if you have an integer you can add 5 to its value automatically like

int value = 10;
changeInt(10);

Now value would be 15. What I don't understand if many times I've seen cases where they aren't just changing the value but somehow allocate a new amount of data dynamic memory wise with something like

void someFunc(int* value)
{
  //something happens here
}

and something else I don't understand is when this has NO NAME for example:

void someFunc(*int)
{
  //something happens here
}

That makes no sense to me. Can someone kindly explain this? Thank you guys so much!!