Spectroscopy is the analysis of electromagnetic spectrum

Atomic spectroscopy , is the analysis of absorption spectrum and emission spectrum of an atom

• These spectrums are due to electronic transitions of outer shell electrons as they rise and fall from one electron orbit to another.
• These electronic transitions release energy in the form of electromagnetic waves with distinct frequencies.
• Atoms have distinct x-ray spectra that are attributable to the excitation of inner shell electrons to excited states.
• Atoms of different elements have different spectra and therefore atomic spectroscopy allows for the identification and quantitation of a sample’s elemental composition
• Emission spectra are produced when electrons of atoms drop down to a lower energy level, after first being excited to a higher level, and release photons of a particular frequency
• An absorption spectra of an element is the negative of the emission spectra for the same element.

Example of Hydrogen Emission Spectrum (in visible region of EM waves)