Carry-on baggage or (hand) baggage is baggage which is small (enough) to fit into the lockers in the cabin of the (plane). On easyJet you are allowed to take one piece of hand baggage into the (cabin) with you. You do not have to (pay) for this. However, if you have (extra) pieces of luggage or items which are too (bulky) to fit into the lockers, they will have to be (checked) in and put into the (hold) of the plane. And, of course, you'll have to pay an additional (charge).