Memory Map:
Memory map is a diagrammatic representation of how memory is organized in a computer system. It shows the physical locations of different memory components such as RAM, ROM, cache memory, and memory-mapped I/O devices. The memory map is typically fixed and cannot be changed by the user program.

Why can't be changed by the user program?
- Hardware Configuration: The memory map is determined by the hardware configuration of the computer system. It is set by the manufacturer and cannot be altered by the user program. Changing the memory map would require changing the physical hardware layout, which is not possible through software.
- System Stability: Altering the memory map can lead to instability in the system. The memory map is designed to ensure efficient data access and proper functioning of the system. Changing it can cause conflicts, data corruption, or system crashes.
- Security Concerns: Modifying the memory map can create security vulnerabilities in the system. It can potentially allow unauthorized access to sensitive areas of memory or compromise the integrity of the system. To prevent such risks, the memory map is kept immutable by user programs.
- Operating System Control: The memory map is controlled by the operating system, which manages the allocation and access of memory resources. User programs are restricted from directly manipulating the memory map to maintain system integrity and prevent unauthorized access.
In conclusion, the memory map is a critical component of a computer system that cannot be changed by the user program due to hardware constraints, system stability concerns, security risks, and operating system control.