According to the latest observational evidence, ordinary matter, including stars, planets, dust and gas, only make up a tiny fraction of the universe (5%). The rest is the elusive dark matter (~25%) and dark energy(~70%).
Dark energy: A mysterious (and as yet hypothetical) form of energy which is spread out uniformly throughout space (and time) and which has anti-gravitational properties: it is one of the possible explanations for the current accelerating rate of expansion of the universe.
Dark matter: Matter not visible to us because it emits no radiation that we can observe, but it is detectable gravitationally.
Hydrogen & helium gas: Hydrogen and Helium are the most abundant element in the universe. This element is found in great abundance in stars and gas giant planets.
Star: A ball of mostly hydrogen and helium gas that shines extremely brightly. Our Sun is a star.
Neutrino: A small particle that has no charge and is thought to have very little mass. Neutrinos are created in energetic collisions between nuclear particles. The universe is filled with them but they rarely collide with anything.