I am a lot more familiar with right libertarians. In the USA these would be called true libertarians. They are economically laissez faire and socially extremely tolerant. Economically they want very low taxes and only for funding absolute fundamentals like military and justice systems. They want almost everything else privatized. Socially they want almost everything legal, only things that directly hurt others should be illegal. This means legal porn of all sorts to view, drugs, lowest possible reasonable age of consent, prostitution, guns, no government mandated ages for drinking alcohol etc. The main difference between anarchist and libertarian positions is that libertarians want a weak centralized government with little tax, whereas anarchists want complete decentralization with no tax, they want defense and police and justice to be decentralized and privatized as well.
I can't speak for all the left libertarians, but they are like a mixture between economic socialism and social freedom. They want the same social freedoms as right libertarians, but they also think that people have rights to a lot of social services like education, healthcare, etc, so they still want taxes. They wouldn't fund much military spending for wars or war on drugs or other frivolous bullshit, but would divert that spending to education and social services etc, rather than eliminate it. A lot of younger liberals probably fall into this category. I'm not entirely sure how they distinguish between anarchism and libertarianism. Also, some anarchist groups that could be thought of as right call themselves left for various technical reasons.