Meet the CPU Registers

Registers are tiny storage locations inside the CPU. They are lightning-fast and essential for all calculations and data movement.

Common x86 Registers

• eax, ebx, ecx, edx: General-purpose registers
• esi, edi: Used for string and memory operations
• esp, ebp: Stack pointer and base pointer

Memory Access

NASM allows you to read from and write to memory using operands and addresses. Data can be moved between registers and memory with the mov instruction.

Example

mov eax, [myVar]   ; Load value from memory
mov [myVar], ebx   ; Store value into memory

Why Are Registers Important?

• They make your code super fast.
• You must manage them carefully — using the wrong register can cause bugs.

Real-World Analogy

Think of registers as your computer's "scratchpad" for doing calculations, while memory is like a giant notebook you can store things in.

Understanding registers and memory is the key to mastering NASM!