Are EDX and DX the same register?

assembly, x86

Solution

DX is simply the lower 16b of EDX :)

mov EDX, 0x1;         --> DX = 0x1
mov EDX, 0x12345678; --> DX = 0x5678

Problem

Sorry for the ignorant question, but I'm rather confused about x86. Is EDX essentially the same register as DX? I understand EDX is 32 bit while DX is 16 bit. If I move 0x1 to EDX would 0x1 also be in DX?

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