1. Atomic Spectra
As atoms gain energy their electrons can be excited and absorb energy in discrete amounts called quanta and produce absorption spectrums.
As atoms lose energy their electrons can release energy in discrete amounts called quanta and produce emission spectrums.

2. Hydrogen spectra
Any movement down to the n=1 state (ground state) will produce UV light and it is called the Lyman Series.
Any movement down to the n = 2 state will emit a photon of energy producing light in the visible spectrum and it is called the Balmer series.
Any movement down to the n = 3 state will emit a photon of energy producing light in the infrared spectrum and it is called the Paschen series.