A friend asked me to define anarcho-primitivism and nihilism in just three sentences, and I thought that was a good exercise in coming up with a concise description without getting mired in all the details. It seems like a good question for a 101 site, and I don't recall seeing it ever on here.
So - in three sentences how would you describe:
- Anarcho-syndicalism
 - Anarcho-communism
 - Mutualism
 - Anarcho-primitivism
 - Nihilism
 - Egoism
 - Illegalism
 - Insurrectionary anarchism
 
I know this is not an exhaustive list of tendencies, so if there are others people want to add, maybe do so in the comments?