Some stuff I dug out which helped me to understand it better:
Libertarianism refers to political philosophies which emphasize freedom, liberty, and voluntary association. [...]Libertarians generally advocate a society with a government of small scope relative to most present day societies or no government whatsoever.
They have certain moral powers to acquire property rights in external things.
In the 1950s many with "Old Right" or classical liberal beliefs in the United States began to describe themselves as "libertarian."
Around the turn of the 21st century, anarchism grew in popularity and influence as part of the anti-war, anti-capitalist, and anti-globalisation movements.