It's nicknamed the damn particle or particle of God. In 1964 British researcher Peter Higgs deduced its existence but lacked the means to prove it. According to his theory, the Higgs boson would be the keystone of the fundamental structure of mater.
Alexandre Zabi, physicist at the National Centre for Scientific Research, explains the Higgs particle: "The matter around us that we know from the periodic table are living compounds made out of these elementary particles."
Understand that all matter around us is composed of molecules, which is, itself, composed of atoms. Which themselves are composed of a nucleus and electrons, that revolve around. Within this nucleus, there are protons and neutrons that contain quarks that are bound by gluons. That's what is meant with elementary particles.
"But what we can't understand is how these elementary particles have mass, where does this mass come from, what is it's origin. And so Mr. Higgs, in collaboration with several others, formulated a possible explanation for the origin of this mass, which is the existence of a Higgs field, through which the particles move and gain mass."
The physicist Higgs didn't think to see it in his lifetime, but on 4 July 2012 his fellow scientist working at the Large Hadron Collider in Geneva, Switzerland announced the discovery of a previously unknown particle which could in fact turn out to be the Higgs boson. Further analysis is needed, but the formal discovery of this theoretic particle will have profound impact on our understanding of the universe.
Wikipedia on Higgs Boson