What does ds mean?

Question

When debugging with x64dbg I sometimes see mov ss:[address] 0xAA, I know that this means: move 0xAA into memory at specified address.

But what does

mov ds:[address] 0xAA

mean?

Answer 1

The ds means "data segment" register in x86 architecture, while ss states for "stack segment" register. You would probably want to read link for more comprehensive description. When you see

mov ds:[address], 0xAA,

it means "move 0xAA to address address in data segment", that is segment pointed by the current value of ds register. Similarly with every other segment register.

In x64 architecture segment registers are ignored.