The penteconters emerged in an era when there was no distinction between merchant and war ships. They were versatile, long-range ships used for sea trade, piracy and warfare, capable of transporting freight or troops. A penteconter was rowed by fifty oarsmen, arranged in two rows of twenty-five on each side of the ship. A midship mast with sail could also propel the ship under favourable wind. Penteconters were long and sharp-keeled ships, hence described as long vessels (, nḗes makraí). They typically lacked a full deck, therefore they were also called unfenced vessels (, áphraktoi nḗes).