The South Geographic Pole is the axis of rotation of the Earth, and the goal of the expedition. It is located at 90 degrees South latitude. Bernard Voyer and Thierry Pétry reached it on January 12, 1996. At that specific point there is no south anymore: no matter which way you turn, you’re facing north!
The South Magnetic Pole is the pole that attracts the compass needle, and it is in constant motion. It is located off the coast of Terre-Adélie at the moment, 2 000km from the South Geographic Pole.
The Geomagnetic South Pole is where the south magnetic pole would be if the Earth were a magnetically homogenous sphere. It would be located at 78 degrees South latitude and 111 degrees East latitude.
The pole of inaccessibility is the farthest point from the coast of the continent: 1 700km from the shore, at 82 degrees South latitude, 54 degrees East.
The cold pole is the coldest spot on the globe, with a record of -89.2°C. The Russian scientific base, Vostok, is located there.