Assembly Memory Segment Layout (Little Endian) - What does the "add" instruction do?

For example, on the first add instruction (add eax, 3), it moves the pointer for eax 3 spots to the right.

Thus, EAX = 12, 17, A3, 00. (This I understand)

But, on the second add instruction (add ebx, 5), it actually adds the value 5 to ebx, making EBX = 12, 17, A3, 05.

Why is that?

ANSWER:

varl var2 var3 dd 179 db 0A3h, 017h 012h bca var1 eax. mov add eax, mov ebx r [eax] add ebx 5 mov [varlj ebx B3 00 00 00 A3 17 12 62 63 61 var1 Va Va (4) (3) (3)