Baltic Sea and ships

Nothing. A destroyer is a type of warship. There are also aircraft carriers, missile cruisers and torpedo boats, amphibious ships, frigates, corvettes, submarines, air defense ships, PLO, patrol ships, minesweepers, support ships, floating bases, supply ships, rescue support, research ships. And then there are icebreakers, tugs, barges, tankers, aquarians, non-winding demagnetization stations, floating cranes, blockshkivs, killectors, scows and many other interesting things.