Can someone show me a website that talks about spectrums of elements. Including why they're all different, like basic information of spectrums. The why, how, and what.

Answer 1

http://en.wikipedia.org/wiki/Emission_spectrum

All are different because the different elements have different electrons in different energy levels; therefore, when the (an) electron moves from one excited state to another state, the energy levels difference is not the same.