--Hopefully this question does not dublicate another--

In [this][1] question Tom Goodwillie pointed out, that the 'atlas part' of
the definition of a smooth manifold can be redefined in terms of
sheaves. How is that done?

I assume it is something along the line: "An atlas is a sheaf on the
site of cartesian spaces (the site with objects $\mathbb{R}^n$, such
that ..."

Can someone clarify this point?


  [1]: http://mathoverflow.net/questions/88056/is-there-a-sheaf-theoretical-characterization-of-a-differentiable-manifold