Nazism, Naziism, or National Socialism in full (German: Nationalsozialismus), is the ideology and practice associated with the 20th-century German Nazi Party and state as well as other related far-right groups. It was also contemporaneous or promoted in other European countries, particularly those with large ethnic German communities such as Czechoslovakia, Hungary, Romania and Yugoslavia Usually characterised as a form of fascism that incorporates scientific racism and antisemitism, Nazism originally developed from the influences of pan-Germanism, the Völkisch German nationalist movement and the anti-communist Freikorps paramilitary culture in post-First World War Germany, which many Germans felt had been left humiliated by the Treaty of Versailles.
German Nazism subscribed to theories of racial hierarchy and social Darwinism, asserted the superiority of an Aryan master race, and criticised both capitalism and communism for being associated with Jewish materialism. It aimed to overcome social divisions, with all parts of a racially homogenous society cooperating for national unity and regeneration and to secure territorial enlargement at the expense of supposedly inferior neighbouring nations. The use of the name “National Socialism” arose out of earlier attempts by German right-wing figures to create a nationalist redefinition of “socialism”, as a reactionary alternative to both internationalist Marxist socialism and free market capitalism. This involved the idea of uniting rich and poor Germans for a common national project without eliminating class differences (a concept known as "Volksgemeinschaft", or "people's community"), and promoted the subordination of individuals and groups to the needs of the nation, state and leader. National Socialism rejected the Marxist concept of class struggle, opposed ideas of equality and international solidarity, and sought to defend private property.
The Nazi Party was founded as the pan-German nationalist and antisemitic German Workers' Party in January 1919. By the early 1920s, Adolf Hitler had become its leader and assumed control of the organisation, now renamed the National Socialist German Workers’ Party (Nationalsozialistische Deutsche Arbeiterpartei) in a bid to broaden its appeal. The National Socialist Program, adopted in 1920, called for a united Greater Germany that would deny citizenship to Jews or those of Jewish descent, while also supporting land reform and the nationalisation of some industries. In Mein Kampf, written in 1924, Hitler outlined the virulent antisemitism and anti-communism that lay at the heart of his political philosophy, as well as his disdain for parliamentary democracy and his belief in Germany’s right to territorial expansion.
In 1933, with the support of more traditional right-wing conservatives, Hitler became Chancellor of Germany and the Nazis gradually established a one-party totalitarian state, under which Jews, political opponents and other "undesirable" elements were marginalised, harassed and eventually imprisoned and killed. Once in power, Hitler purged the remnants of the party’s more socially and economically radical factions in the Night of the Long Knives and, following the death of President Hindenburg, ultimate authority became increasingly concentrated in his hands, as "Führer", or leader. Following the Holocaust and German defeat in the Second World War, only a few fringe racist groups, usually referred to as neo-Nazis, still describe themselves as following National Socialism.
Nazi is just an acronym for the National Socialist Party, as it is in German: Nationalsozialistische Deutsche Arbeiterpartei. The term had no negative connotations in Germany, or indeed in the rest of the world, until the time of the Second World War.
Nazism is the name given to the political ideology and subsequent regime of Adolf Hitler, which ruled in Germany from 1933 to 1945. Although Nazism is often called "fascism", it does differ from generic fascism, as the term is used today, and also from Fascism, which is the name given to Mussolini's regime in Italy around the same time. Nazism's main points of emphasis were the racial superiority of the "Aryan" people, the annihilation of the Jews, seen as racially inferior, the aggressive foreign policy, especially in relation to East European countries, seen as genetically inferior and the importance of the "Fuehrer" (i.e. Hitler) as the head of state.