Light is the fastest thing in the universe it travels much faster than sound.
The first thing that i am prety sure of is light speed.
DarkPrince of Awesomeness
1. Fastest thing in the universe is supposedly the expansion of space itself
2. After that come all photons (electromagnetic waves including light) in pure vacuum (space not affected by gravity in general relativity).
2.1. Gravity waves also supposedly travel with the speed of light.
3. #3 would then be cosmic ray particles. Fastest one ever detected, the so called "The Oh-My-God Particle" with the energy of (3.2 +/- 0.9) * 10^20 electron volts and the speed 0.9999999999999999999999951 c, 1.467 * 10^(−15) metres per second slower than light. After traveling one light year, the particle would be only 0.15 femtoseconds (46 nanometers) behind a photon that left at the same time.