Chemiluminescence vs. Bioluminescence Luminescence in general, is the term of emission of light from specific substances/objects. Chemiluminescence is the emission of light due to chemical reactions. Bioluminescence on the other hand is the emission light from living/biological organisms such as insects ( this is of course the way I understood them ), but I'm a little bit confused because what is the cause that makes insects emmit light? Doesn't that also have to do with chemical reactions but inside living organisms ? 

Just a clear explanation of the difference  between these two terms  would be helpful.
Doesn't that also have to do with chemical reactions but inside living organisms?


Exactly! That's why there is one scientific society for both phenomena: ISBC - International Society for Bioluminescence and Chemiluminescence ;-)

The thermal reactions, that lead to an excited species which eventually emits a photon are quite similar. From a reactive compound, typically called a luciferine, a four-membered ring, often a dioxetanone is formed. This decarboxylates and gives rise to a molecule in an electronically excited state. In reality, the decarboxylation is often not just a spontaneous process but requires an activator. W. J. Baader at IQUSP in Sao Paulo, Brazil has examined that in great detail.

The luciferines can be quite different compounds, such as  


diaryloxalates (these are used in glow sticks, where the diferent colours come from diferent fluorphores that absorb the initial photon and emit at different wavelength)  
benzothiazole derivatives (firefly)  
triazine derivatives (marine organisms)