Geodetic datum is a coordinate reference system developed to assist surveyors, cartographers and navigators to describe geographic positions.
Historical surveying tools used for measuring distances included the perambulator, Gunter's chain and steel tape, until distance measurement was standardised.
Read about tools that early explorers and surveyors used to measure the height of land.
Historical surveying tools used for measuring angles including the circumferentor and theodolite.
Historical surveying tools used for calculations including the curta and arithmometers.