Objective-C also has the autorelease pool, which allows for a bit more flexibility in that you don't need to pay as much attention to the refcount. You can als

Objective-C also has the autorelease pool, which allows for a bit more flexibility in that you don't need to pay as much attention to the refcount. You can also optimize allocations using zones, which are like mini-heaps that collect a bunch of objects and allow you to release all of them with a single deallocation -- very handy if you have a ton of small objects (like a DAG) where you know for a fact that when the root is deallocated, all the nodes should be freed as well.