The paper presents Raman spectroscopy measurements on single- and few-layer graphene flakes, using a scanning confocal approach to collect spectral data with spatial resolution. The width of the D' line is used to distinguish single-layer graphene from double- and few-layer graphene, with the single peak in single-layer graphene splitting into different peaks in double-layer graphene. These findings are explained using the double-resonant Raman model based on ab-initio calculations of electronic structure and phonon dispersion. The D line intensity is investigated, showing no defects within the flake, but a finite D line response from the edges attributed to defects or translational symmetry breakdown. The study also reveals that the integrated G line signal is correlated with the thickness of the graphitic flake and shifts upward in frequency for double- and single-layer graphene compared to bulk graphite. The D' line width shows a strong contrast between single- and few-layer graphene, making it a sensitive detector for single-layer graphene. The D band, related to elastic backscattering, is used to locally resolve the structural quality of the flake, with the inner part being quasi-defect-free and the edges and steps serving as scatters. The splitting of the D' line is explained within the double-resonant Raman model, which, while qualitatively valid, shows quantitative differences between theory and experiment, particularly in the predicted peak splitting. The study concludes that Raman mapping is a powerful tool for investigating single- and few-layer graphene flakes, with the D' line width being highly sensitive to the transition from single- to double-layer graphene.The paper presents Raman spectroscopy measurements on single- and few-layer graphene flakes, using a scanning confocal approach to collect spectral data with spatial resolution. The width of the D' line is used to distinguish single-layer graphene from double- and few-layer graphene, with the single peak in single-layer graphene splitting into different peaks in double-layer graphene. These findings are explained using the double-resonant Raman model based on ab-initio calculations of electronic structure and phonon dispersion. The D line intensity is investigated, showing no defects within the flake, but a finite D line response from the edges attributed to defects or translational symmetry breakdown. The study also reveals that the integrated G line signal is correlated with the thickness of the graphitic flake and shifts upward in frequency for double- and single-layer graphene compared to bulk graphite. The D' line width shows a strong contrast between single- and few-layer graphene, making it a sensitive detector for single-layer graphene. The D band, related to elastic backscattering, is used to locally resolve the structural quality of the flake, with the inner part being quasi-defect-free and the edges and steps serving as scatters. The splitting of the D' line is explained within the double-resonant Raman model, which, while qualitatively valid, shows quantitative differences between theory and experiment, particularly in the predicted peak splitting. The study concludes that Raman mapping is a powerful tool for investigating single- and few-layer graphene flakes, with the D' line width being highly sensitive to the transition from single- to double-layer graphene.