Two little Lithuanian Jewish boys: Emanuel Rosenthal (2 years old) and Avram Rosenthal (5 years old) in the Kovno ghetto. They were deported to Majdanek and gassed upon arrival. Kovno ghetto, 1944. USHMM

Jewish mother hugging her little daughter while a German Einsatzgruppe shoots her in the head. Ivangorod’s massacre, Ukraine, 1941­–1943. Yad Vashem

Judenstern, 1942–1945. USHMM

The Gate of Death. Entrance to Auschwitz-Birkenau. Stanisław Mucha. Auschwitz-Birkenau State Museum

Gas pellets of Zyklon B. Loboda, 1968. Auschwitz-Birkenau State Museum

Hungarian Jewish men, women and children arriving at Auschwitz. Auschwitz-Birkenau, May-June, 1944. The Auschwitz Album. Yad Vashem

Hungarian Jewish women and children awaiting selection. Auschwitz-Birkenau, May-June, 1944. The Auschwitz Album. Yad Vashem

Hungarian Jewish women and children awaiting selection. Auschwitz-Birkenau, May-June, 1944. The Auschwitz Album. Yad Vashem

Hungarian Jewish women and children walking towards the gas chamber. Auschwitz-Birkenau, May-June, 1944. The Auschwitz Album. Yad Vashem

Hungarian Jewish women and children walking towards the gas chamber. Auschwitz-Birkenau, May-June, 1944. The Auschwitz Album. Yad Vashem

Hungarian Jewish women and children awaiting to be gassed. Auschwitz-Birkenau, May-June, 1944. The Auschwitz Album. Yad Vashem

An old Hungarian Jewish woman carrying a little baby and other three little children walking towards the gas chamber. Auschwitz-Birkenau, May-June, 1944. The Auschwitz Album. Yad Vashem

Jewish Auschwitz prisoner. Number 6.874. Wilhelm Brasse. Yad Vashem

Jewish Auschwitz prisoner. Number 7.537. Wilhelm Brasse. Yad Vashem

Jewish Auschwitz prisoner. Number 7.544. Wilhelm Brasse. Yad Vashem

Pole (non-Jewish Polish) Auschwitz prisoner Czesława Kwoka. Number 26.947. Wilhelm Brasse. Yad Vashem

Gypsy (Roma) Auschwitz prisoner (Z=Zigeuner). Number 63.598. Wilhelm Brasse. Yad Vashem

Glasses from the victims of Auschwitz. Auschwitz, January 1945. USHMM

Hair from the victims of Auschwitz. Auschwitz, January 1945. USHMM

Clothes from the victims of Auschwitz. Auschwitz, January 1945. Auschwitz-Birkenau State Museum

Shoes from the victims of Auschwitz. Auschwitz, January 1945. Auschwitz-Birkenau State Museum

Three children survivors: Romek Wajsman (prisioner number 117098), Janek Szlajtsztajn (prisioner number 116543), and Dawid Perlmutter (prisioner number 116730). Buchenwald. After the liberation. Fotoarchiv Buchenwald © Gedenkstätte Buchenwald und Mittelbau-Dora

Children survivors. Auschwitz, January 1945. Auschwitz-Birkenau State Museum

Baby survivor tattooed. Auschwitz, January 1945. Auschwitz-Birkenau State Museum

Children survivors showing their tattoos. Auschwitz, January 1945. Auschwitz-Birkenau State Museum