text: Q:
  
  How fast data travel wirelessly than in metal?
  
  How fast data travel wirelessly than in metal? does both travel in the speed of light?
  
  A:
  
  Electrical signals basically move at the speed of light in that particular medium. In (copper) wires that is usually around 70% - 90% of the speed of ligth (in a vacuum) or around 200,000km/s - 250,000km/s as opposed to the around 300,000km/s which light travels in vacuum. [Velocity Factor]
  Even the speed of light is not constant as is often referenced. The speed of light in a vacuum is constant and it is the maximum speed to transfer usefull information. Still even light can be slowed down (a recent experiment even stopped it for some very short time article youtube ) and it can even go faster than the vacuum speed (see Faster than light speed).
  Relevant to your question is, that information information travels in the speed of it's medium. Light in glass travels slower than in vacuum. Electricity in copper wires travels slower than c meaning it is slower than "light speed". But it may travel slower or faster in water, iron, etc. It depends on the medium it is traveling through.
  According to How fast does light travel through a fibre optics cable due to reflections and bending of the fibre optics, such signals also travel about 30% slower than the speed of light in vacuum. That means both signals are about as fast as each other.
  Remember that light is also an electro-magnetic wave. Thus is travels at light-speed in vacuum, but in a fibre-optic cable you basically send it through air, while in a copper wire, you send it through copper. 
  As for data transmission, that depends on the transmission frequency, dampening and bandwidth of the signal and medium. 
  
  