The Celebration used to be the old Noordam, there is no internet on a wi-fi basis but there is an internet cafe. The cabin voltage is 110 & 220 but you hair gear is usually dual voltage anyway.
Cabins have hair dryers situated in dressing table draw there is also a hair salon if required at additional cost book early for formal evening if required.
Yes there is an hair dryer in the cabin but anything like curling tonge etc youl need two flat point plugs. Yes there internet onboard on Deck 5 were the libary although it is expensive due to going on ship setelite.