What is the difference between Xray spectroscopy and X Ray diffraction?

Question

I need to know the difference based on their principle, instrumentation and applications.

Answer 1

http://en.wikipedia.org/wiki/X-ray_spectroscopy

X-ray diffraction uses x-rays reflected from a crystalline material to analyze the atomic structure of the crystal. The atoms are so close together that ordinary light wavelengths do not produce diffraction patterns, but x-ray wavelengths can. The diffraction patterns reveal the atomic placements and separations in the crystal.
http://en.wikipedia.org/wiki/X-ray_diffraction

Answer 2

X-Ray Spec. means spliiting the X-ray into a spectrum, knowing it's components. eg when white light spectrum is analysed it gives us Violet, Indigo, Blue, Green, Yellow, Orange, Red.

X-ray diffraction is an analysis of by how much degrees the various components diffract(change their paths or bend). For X-ray diffraction you will need an Excellent Grating, since the wavelenghts associated with X-rays are 10^-10 mts.