title: Difference between cuda.h, cuda_runtime.h, cuda_runtime_api.h
body: <p>I'm starting to program with CUDA, and in some examples I find the include files <code>cuda.h</code>, <code>cuda_runtime.h</code> and <code>cuda_runtime_api.h</code> included in the code. Can someone explain to me the difference between these files?</p>