Explain the motives and key features of technology behind european maritime exploration and expansion

From the 12th century with the development of towns and trade there has been tremendous progress in the field of navigation. ocean expeditions were not possible in rowing boats, in which the ratio of the crew (mainly rowers) to the volume of the hull did not allow the assembly to ship sufficient quantities of supplies. to revolutionary changes occurred as a result of improvements to the ships, especially intense since the thirteenth century. multi-mast square rig and hull design have enabled the flow of the wind. reducing the amount of crew and increases the volume of the hull allowed to take a large amount of supply, particularly of fresh water. new type of  rudder significantly improved maneuverability. the result of a series of inventions boat builder was a new type of ship: nef, karaka and caravel - the first seagoing sailing decoupled from the proximity to the mainland.in the field of navigation progression also occurred since the thirteenth century. using magnetic needle, setting her in a box, constructing a compass, enabling the maintenance of the course regardless of the view of the stars.