"Those who forget the past are condemned to repeat it."

Nearly 6 million European Jews were ruthlessly killed by Adolf Hitler during the second World War. From 1941 to 1945, Jews were methodically murdered in which is still considered to be one of the 'deadliest genocide in human history' Nearly 42,500 detention facilities were used by the Nazis to imprison Jews and carry out flagrant violations of Human rights. Over 200,000 people are estimated to have been Holocaust perpetrators.  Adolf Hitler managed to manipulate his whole nation, that extermination of Jews is the only solution. Giving his nation a notorious tag called 'Nazi Germany'. Personally, Hitler's persona doesn't bother me a lot. The fact that an estimated number of 200,000 odd Nazis involved directly in massacring 6 million Jews was alarming.
Why did Hitler and Nazis hate Jews? 
According to many historians, Jews are merely the victims of 'Scapegoating'. Hitler blamed that Jews ,are responsible for major events like Germany's loss in World war-1 and economical crisis.But by putting the blame on Jews, Hitler created an enemy. Germans believed him blindly, and assumed that Jews are the real problem. It is a perfect example of Mass Hysteria.
"Believing something blindly" That's something us, humans do a lot. Either its religion or king or a dictator. Humans are the victims of manipulation. We keep proving it throughout our recorded history.
Many believe Hitler invented Antisemitism, Its a No. Of course, he didn't invent it. Hitler built on and used Antisemitic ideas that already existed. He was an Austrian and grew up in Vienna where the Mayor was extremely antisemitic and where hatred of Jews was widespread. These episodes led  Hitler and two hundred thousand people to conclude that Jews are destroying their livelihood. They thought its their 'final' solution. During the era of Holocaust, Nazis also targeted other groups because of their perceived "racial inferiority" : Gypsies, the disabled, some of the slavic people (russians), While some persecuted on political,ideological and behavioral grounds; among them communists, Jehovah's witnesses and Homosexuals.  Killing is unacceptable. We don't have any right to take someone's life.
The holocaust is a history of enduring horror and sorrow. It seems as though there was no spark of human concern, no act of humanity, to lighten that dark history.
Auschwitz-Birkenau Belzec Bergen-Belsen,etc and all other concentration camps where millions cried for help, stuck inside those doomed walls, awaiting their fate. They will be remembered forever.
The Holocaust survivor Abel Herzberg has said: "There were not six million Jews murdered; there was one murder, six million times.".
The words of Elie Wiesel, the Nobel laureate and Holocaust survivor, stand as a testament to why we must never forget this dark period of human history:
"For the survivor who chooses to testify, it is clear: his duty is to bear witness for the dead and the living. He has no right to deprive future generations of a past that belongs to our collective memory. To forget would be not only dangerous but offensive; to forget the dead would be akin to killing them a second time. The witness has forced himself to testify. For the youth of today, for the children who will be born tomorrow. He does not want his past to become their future." Elie Wiesel, Night, Preface to the New Translation (New York: Hill and Wang, c2006), page xv.
RIP- to those who died.
 * -  Photo taken at Yad Vashem, the Holocaust museum in Jerusalem. This image shows a young Jew looking up into the Hall of Names, an exhibit in the museum.