1.5m width twill carbon fibre cloth roll

 1.5m width carbon fiber cloth and carbon fiber material

Carbon fiber starts off as an organic material (which, by nature, includes carbon). The material is stretched into very thin strands. These strands are then heated to extremely high temperatures, which shakes all of the non-carbon atoms off of the strands, leaving them as pure carbon. These strands are then bundled up into rovings, which are woven together to create carbon fiber cloths. The rovings are named according to how many strands of carbon fiber are present in each "bundle". Common ones you will see are 1k, 3k, 6k and 12k.