Simple: anarchism refers to the belief that governments are unnecessary and/or unjustified; socialism refers to the opinion that the means of production ought not to be owned by private individuals or entities.
> Second, 'libertarian' means 'anarchist' in the same way 'Republican/conservative' means 'fascist' and 'Democrat/liberal' means 'socialist'. Anarchist/Fascist/Socialist are extremes, and libertarian/conservative/liberal are regions along the spectrum. IMO.
Depends who you ask! These words all have different meanings across societies and cultures. I don't think these ideologies can be collapsed into points or regions along a spectrum.