Tsarin daidaiton yanayin kasa ( GCS ) tsarine wanda yake kunshe da ainihin wurare a Duniya ( matsayin wuri ). GCS na iya ba da matsayi: azaman tsarin daidaitawa mai amfani ta hanyar amfani da latitud, longitude, da kuma bisa ; kamar yadda taswirar taswirar da aka tsara akan jirgin, mai yiwuwa gami da tsayi; kamar yadda yake a duniya, mai daidaita duniya ( ECEF ) haɗin haɗin Cartesian a cikin 3-sarari ; azaman saitin lambobi, haruffa ko alamomi din n samar da geocode . A geodetic da daidaito da kuma lambobin taswira , tsarin daidato yana hawa kuka sai ya hade. and map coordinates, the coordinate tuple is decomposed such that one of the numbers represents a vertical position and two of the numbers represent a horizontal position.   A sabuwar dabara na wani yanayin daidaita tsarin da aka kullum yaba wa Eratosthenes na Bakurane, waɗanda suka haɗa da yanzu-rasa yanayin kasa a Library of Alexandria a cikin karni 3rd BC. Aarni ɗaya bayan haka, Hipparchus na Nicaea ya inganta akan wannan tsarin ta hanyar tantance latitude daga ma'aunin taurari maimakon tsawan rana da kuma ƙayyade tsawo ta hanyar lokutan fitowar wata, maimakon lissafin mutu'a .