Dirk Hartog was a 17th-century Dutch sailor and explorer. Dirk Hartog's expedition was the second European group to land in Australia and the first to leave behind an artefact to record his visit, the Hartog Plate. His name is sometimes alternatively spelled Dirck Hartog or Dierick Hartochszch. Ernest Giles referred to him as Theodoric Hartog. The Western Australian island Dirk Hartog Island is named after Hartog.

Hartog Plate or Dirk Hartog's Plate is either of two pewter plates, although primarily the first, which were left on Dirk Hartog Island during a period of European exploration of the western coast of Australia prior to European settlement there. The first plate, left in 1616 by Dutch explorer Dirk Hartog, is the oldest-known artifact of European exploration in Australia still in existence. A replacement, copying the text of the original plus some new text, was left in 1697 – the original dish returned to the Netherlands, where it is on display in the Rijksmuseum. Further additions at the site, in 1801 and 1818, led to the location being named Cape Inscription.