A carrier-capable aircraft is one designed to operate from conventional aircraft carriers. Compared to land-based aircraft, they have reinforced airframes to withstand the sudden acceleration of catapult takeoffs, and the even more sudden deceleration of arrested landings. It is expected they will be exposed to salt water, so they have appropriate protective coatings.
The strong trend is to make such aircraft more fault-tolerant than land-based aircraft that have more options for emergencies. For example, where a lightweight land-based fighter aircraft such as the F-16 has a single engine, its Navy counterpart, the F-18, has two engines; if one fails, the pilot has options other than going down into the sea.