This document summarizes memory management techniques in Python. It discusses how Python uses both reference counting and generational garbage collection. Reference counting tracks the number of references to an object and deletes the object when the count reaches zero. However, reference counting alone cannot detect cyclic references. Therefore, Python also uses tracing garbage collection to periodically detect and delete cyclic references. The tracing GC operates across multiple generations of objects, with the assumption that most objects die young and are contained in earlier generations.