‘Medieval and Renaissance learning and practice’ describes the techniques used by the three major cultures of ambitious development in navigation—Chinese, Arab, and European. It begins with the ‘Arab compass’ that used horizon astronomy, the kamāl, and latitude sailing. It then describes the Chinese use of the magnetic compass, believed to have been first used at sea during the 11th century. By the 15th century, the Chinese were using the compass alongside dead reckoning and so could choose between coastal and latitude sailing. The use of portolan sea charts and sets of tables (toleta) in the Mediterranean and quadrants and astrolabes in the Atlantic in the 14th‐15th centuries is also described.