What it is: Great destruction and loss of life, especially by fire. 'The Holocaust' (sometimes also called 'the Shoah') refers to the genocide of up to 6 million European Jews carried out by the Nazi regime in Germany between 1940 and 1945.

What it means: When Hitler became dictator of Germany in 1933, legalised persecution and exclusion of the Jewish population began almost at once. It was almost complete by 1939, and Jews were being physically attacked and murdered as well. Then the Second World War created conditions in which genocide could be committed. Hundreds of thousands of Jews (together with Gypsies, homosexuals, left-wing political activists and other targeted minorities), both from Germany and from the countries Germany invaded, were gradually rounded up and interned in over 1,600 concentration camps. Some were sent to labour camps (there were over 900 of these). They were forced to work as slaves in almost every kind of industry until they died from starvation, exhaustion, or execution for trivial offences. The first gas chamber was set up in 1939. These were first used to kill people with mental disabilities, then (from 1941) for the mass extermination of Jews. Six death camps were built: Auschwitz, Belzec, Chelmno, Majdanek, Sobibor and Treblinka, all with access by rail. They were designed and equipped for slaughter on an industrial scale: by the end of 1944 up to 5,400,000 Jewish men, women and children had been methodically killed there. Jews were also killed by mobile killing battalions created for the purpose: most were shot beside ditches which then became their mass graves. In the concentration camps they died of starvation and disease. When, in 1945, British soldiers discovered the camp at Bergen-Belsen, they found 10,000 corpses and 60,000 prisoners famished, ill or dying. One soldier wrote home: 'We went into a hut. The sight that met us was shocking. There were about 200 people lying on the floor. Some wore a few battered rags, some wore no clothes at all. They were huddled together. The floor was covered in faeces and soaked in urine, and the people lying on the floor were in the same state - they all had severe diarrhoea and were too weak to move. Here and there a dead person could be seen lying between two living ones.'

Think about it: There are many things to think about, but above all there is the question of responsibility. Some of the leaders of the Nazi genocide programme committed suicide, or were captured and taken to trial, or escaped to live under assumed names in exile. But the leaders, and the many armed men who worked for them, were not the only people responsible. Thousands of ordinary men (and women) were clerks and officials who enforced the laws which deprived Jews of their citizenship, property and jobs. Many thousands more worked on the railways, without which the Holocaust could almost certainly not have been carried out. And what about the factories where the Jewish slave labourers toiled? - only a handful have acknowledged their part in the Holocaust, and only after several decades. It's important to think about why any of these people like ourselves - imagine yourself as one of them - might have done what they did. Fear? Prejudice? Turning a blind eye? (There were people who did help some Jews to escape, or hid them - but these people were few, and faced punishment when found out.)  It's also important to think about the long arm the Holocaust extends into the present day. This is what a woman called Sara, whose parents survived the Holocaust, wrote in 2002: 'The Holocaust has been the defining feature of my life. It could not have been otherwise. I lost over a hundred members of my family and extended family in the Nazi ghettos and death camps - people about whom I have heard so much, people I never knew'. In Israel in the 1980s Sara saw first-hand the way many Palestinians were treated by Israelis. To her this echoed the way Jews had once been treated: though on nothing like the same scale, it was the same 'in principle, intent and impact: to humiliate and dehumanise'. The Israeli occupation, Sara said, 'spoke the same message: the denial of one's humanity'. Sara's mother had refused to go to Israel. She believed that 'tolerance, compassion and justice cannot be practised when one lives only among one's own'. She wanted to live 'as a Jew in a society where my group remained important to me but where others were important too'. Think about the actions brought about by Jewish determination 'never to be slaughtered again'. Think about what Sara and her mother might say about persecution and repression, anywhere.