Computers use the von Neumann stored program concept.
Define the term stored program concept.
Mark scheme
Award one mark for any of the following up to a maximum of two marks:
- Program instructions are stored in main memory/RAM (1)
- The data used by the program is stored in main memory/RAM (1)
- The CPU fetches/reads instructions from main memory to execute them (1)
- The program can be run without the instructions being input again (1)
Allow 'the program is stored in memory' for one mark.
Do not accept answers about programs being stored on secondary storage, such as a hard disk or USB memory stick.
Do not accept answers that only describe the von Neumann architecture (e.g. having a CPU and memory) without stating that instructions are stored in main memory.
Example answers and how they were marked
Both the program instructions and the data the program uses are held in the same main memory, and the CPU fetches these instructions from memory to execute them.
Why: Instructions stored in main memory (1) and the CPU fetches instructions from memory to execute them (1).
Program instructions are stored in main memory.
Why: Instructions stored in main memory (1). No second point about data being stored in the same memory or about the CPU fetching instructions.
The program is saved on the hard disk so that it can be loaded into RAM when the user runs it.
Why: A near-miss about secondary storage, which the mark scheme says not to accept; the stored program concept is about instructions being held in main memory.