The Sloop is a sailable ship in Sea of Thieves. It is a single mast vessel with a maximum crew capacity of two. Sloops are highly maneuverable but only carry two cannons on board. They trade power and durability for maneuverability and simplicity. Due to their smaller size, Sloops are easier to repair than the larger Galleons.
They are capable of being sailed solo but operate best with two players. Sloops are recommended for experienced pirates only, as they're an easy target for hostile crews using the devastating Galleon. A notable feature about the Sloop is it's operating efficiency compared to the Galleon, as raising and turning the sails, along with raising the anchor, takes much less time than on the Galleon.
Note: There is no difference between the 1 person sloop and the 2 person sloop other than the number of players on board.