Memory leaks are blocks of allocated memory that the program no longer references. Leaks wastes paceby filling up pages of memory with inaccessible data and waste time due to extra paging activity. Leaked memory eventually forces the system to allocate additional virtual memory pages for the application, the allocation of which could have been avoided by reclaiming the leaked memory, also we can say that in other words Retaining And Releasing are not properly used then RetainCount for AnObject doesn’t reach 0. It doesn’t crash the application.