DirectX swap chain buffer and depth stencil buffer creation (they differ?)

Hi there,

I noticed during my recent reading that in the book I have the swap chain buffers (of which there are two) and the depth stencil buffer (of which there is only one) are both defined as resources. Has a certain type I can't remember what it is. Essentially almost like a texture.

However there seems to be extra steps involved for making the depth stencil buffer. A resource is declared and defined, then a function is called on it which I think is called CreateCommittedResource which puts the buffer in a heap of some kind on the GPU.

Then just as you do with the two buffers in the swap chain you create a view (descriptor) to/for them. For the swap chain you create a render target view for each buffer and for the depth stencil buffer you create a depth stencil view.

So why are they treated differently? I wonder is the function that creates the swap chain also secretly responsible for making a committed resource for each buffer as well, but that just isn't apparent in the code. Or are swap chain buffers not the sort of resource that lives on the GPU?

Any ideas? Thanks :)