>>402550Nazi is (so-called) National Socialism, politics deriving from the old NSDAP party of Germany under Adolf Hitler.
While a lot of people who don't learn about politics think it's the same as fascism, it's only a form of it (just like Bolshevikism in the USSR was only a form of socialism, there are many others that are different). Fascism is authoritarian, nationalist and pro-imperial which I see as undesirable, but by itself isn't quite as retarded as NatSoc. NatSoc is more focused on racism, anti-semitism and eugenics, all the bullshit about Aryans and that is NatSoc. They take it as step further.
On the other hand, there are some fascists, even if rare, who are socially progressive (could easily agree with many "leftists"), and other variations like Strasserists, who Hitler purged, and Third Positionists who are fascist but economically much closer to socialism.
Again, I think they're all bullshit, but there is a difference, and saying 'Nazi = Fascist = /pol' is just overgeneralizing. By the way, large amounts of /pol/ (and even some people using the Nazi flag here) are anti-Nazi, more like American conservative liberalism with racist elements. /pol/ is a wide range of conflicting opinions, it's just that most of them suck and most of them have no idea what they're talking about.
Unrelated, but here's a nice thread-relevant video useful for new to left people.