Le yunithi inee-coordinate ezintathu, ekwabizwa ngokuba yi-dimension, ngumatshini wokulinganisa ngokuchanekileyo, obizwa ngokuba yi-CMM. Sisixhobo sokulinganisa ngokuchanekileyo esisebenzayo esaphuhliswa ngeminyaka yoo-1960. Yavela ngenxa yokwenziwa kwezixhobo zomatshini ezizenzekelayo kunye nezixhobo zomatshini ze-CNC ngokusebenza kakuhle, kunye nesidingo sezixhobo zokulinganisa ezikhawulezayo nezithembekileyo zokucutshungulwa kweendawo ezimile ngendlela enzima ngakumbi.

Okwangoku, umlinganiselo we-three-coordinate usetyenziswe kakhulu kumashishini ahlukeneyo afana nokuvelisa oomatshini, ishishini leemoto, ishishini le-elektroniki, ishishini leenqwelo moya, njl.njl., kwaye uye waba sisixhobo sokulinganisa esichanekileyo nesiyimfuneko sokuhlola amashishini anamhlanje kunye nolawulo lomgangatho. Kwii-gages zethu ezikhethekileyo ezingezizo ezisemgangathweni, umlinganiselo we-three-coordinate sisixhobo sokuvavanya esiyimfuneko. Emva kokuba sifumene imizobo yemveliso yomthengi kwaye siyile isicwangciso se-gage esihlangabezana neemfuno ezifanelekileyo zemveliso kwaye umthengi wanelisekile, kuyimfuneko. Qala amanyathelo okucubungula kwinqanaba elilandelayo, emva koko kufuneka sisebenzise umlinganiselo wethu we-three-coordinate, kuba ukuchaneka kwesixhobo ngokwaso kuphezulu kakhulu, ngoko sisebenzise ukuvavanya ukuchaneka kwenxalenye nganye ye-gage yethu, kuba i-gage ngokwayo iqinisekisa ukuchaneka kwezixhobo zethu zokuhlola. Umzekelo, indawo ethile ye-gage, ukuthamba kunye neprofayili yayo ziquka ezinye iindawo zemoto. Sonke singafumana ubungakanani bokwenyani ngokubona umlinganiselo we-coordinate.