Stored Program Concept

The stored program concept refers to how programs are loaded from memory and executed.  Initially they will be contained in secondary storage (e.g. a hard drive or on a DVD).  The sequence of instructions that make up the program are then transferred to main memory (i.e. the RAM).  As they are required these instructions are fetched and decoded, and subsequently executed by the processor.  These instructions within the main memory can be replaced at any time.  Each instruction is treated as data by the processor.