The sharp series is a series of spectral lines in the atomic emission spectrum caused when electrons jump between the lowest p orbital and s orbitals of an atom. The spectral lines include some in the visible light, and they extend into ultraviolet. The lines get closer and closer together as the frequency increases never exceeding the series limit. The sharp series was important in the development of the understanding of electron shells and subshells in atoms. The sharp series has given the letter s to the s atomic orbital or subshell. The sharp series has a limit given by