**Abstract**

Raman spectroscopy is employed to study a myriad of complex materials due to the coupling of different resonances process and microscopic resources. For instance, vibrational and electronic aspects of carbon allotropes can be deeply investigated by resonance Raman spectroscopy. By selecting the appropriate laser line, it is possible to monitor different aspects of the samples, such as the behavior of metallic or semiconducting tubes and the graphene with different layers or chemical modifications. In this chapter, the potentialities of Raman technique will be exemplified in some examples obtained in our group about the characterization of carbon nanotubes and graphene. For instance, the doping process of nanotubes, carbon tube interactions with molecular magnets, and inhomogeneity of graphene samples will be discussed.

**Keywords:** Raman spectroscopy, Raman imaging, carbon nanotubes, graphene, modification
