What they are mentioning on that site are the different varieties of carbon and the different lay up processes. Wet carbon is when you apply resin to dry carbon (i.e. it is off a roll). This is messy and even under a vacuum (which to an extent can control any excess resin (weight) some pinholes of air can cause weaknesses.
The other processes mentioned are prepreg i.e. the carbon is pre pregnated with resin. It is stored in a freezer and simply laid onto the mould. It is stronger mainly because exactly the right amount of resin is used and it is fully wetted out once laid. The only downsides are that curing temps are often 100 degrees c plus and its a lot of money.