Terminology
Retain cycles: This is the state when two objects hold weak references to one another. Since the first object’s reference count cannot be 0 until the second object is released, and the second object’s reference count cannot be 0 until the first object is released neither object can be released! It is self-evident that it is not possible to create retain cycles with value types, as they are passed by value.
Memory footprint: the amount of memory that a program uses or references. The more resources that are used, the larger the footprint. If objects are not released the occupied memory will grow, leading to memory warning and crashes.
Memory leak: A memory leak is a portion of memory that will never be used, yet is…
