Regular selections among Jews deported to Auschwitz for extermination began in mid-1942 (rail ramps). When the train arrived, the SS men ordered everybody to go outside. While forming up into separate columns of men and women with small children, the deportees listened to the assurances of the SS men that they would be placed in a labor camp and that trucks would carry the old and infirm there, while the others walked. The matter‑of‑fact tone of the speech and the feigned concern for the elderly usually had a calming effect.

SS physicians made the decision to send individual deportees to destruction or to work in the camp on the basis of their own impression of the person’s physical condition and age. Selection lasted from one to several hours, depending on the size of the transport. Initially, the trucks took the doomed to the Little Red or Little White House or, from the spring of 1943, to the new, larger gas chambers. From mid-1944, selections took place on the rail ramp inside the Birkenau camp.

(Mini dictionary of terms from the history of Auschwitz)