Libertarian is also known as Classical Liberalism, Randian/Randianism (after Ayn Rand), but is just the belief that liberty should be the core principle of their philosophy, seeking to maximize political freedom and autonomy, emphasizing freedom of choice, voluntary association and individual judgment (and responsibility/accountability). In Europe, this would be left wing, in the U.S. it is right wing.
The basics are Thomas Jefferson was a libertarian, as were most of the founding fathers. Which means most libertarians are conservatives, in that they want to go back to when the U.S. had more individual liberties, smaller federal government (more state governmental control), lower taxes, more opportunities, and less regulations. There's a huge spectrum of how far back, and in what areas first. And it's important to remember that this is opposed to most European conservatives: where when they want to go back, it's often back to more imperial or monarchistic autocracy or centralized control (our histories are different, so back means different things).
Also, libertarianism is a philosophy that can't always be achieved. (At least to the more pragmatic/realistic). So it's something to be strived towards, with gaps. Jefferson felt we shouldn't go into national debt... then the Louisiana purchase opportunity came up, and he said, "screw that, I'm buying the land rights!". He also had slaves, while hating the institution and wanted to figure a way out of the economic trap it was for both sides. Things like that.
Libertarians are "classical liberals". Basically, what liberal (where libertarian came from) originally meant is, "Liberty": maximizing autonomy, freedom of choice, and the primacy of individual judgment. Around the turn of the 19th century, American progressive socialists started to usurp the name liberal, and re-invent it as meaning themselves (heavy state control and what federalism used to mean): even-though everything the left stood for was the opposite of classical liberalism. Since this didn't take root in Europe, "liberal" means opposite things in the U.S. and Europe (generally American libertarian is what Europe means with liberal -- though Americas misuse of the term has muddied the waters as Europeans have started using it wrong as well).
Here's a list of things that are, or are not, Libertarian -- and what the term or philosophy means.
|"Liberals" aren't liberal any more - Liberalism traditionally means liberty (tolerance for). In America, it has grown to mean the opposite. Classical liberals (libertarians) are liberal in both economics, and social arenas. Social liberals are liberal only in Social areas, but not in economic ones. Their economic authoritarianism, in the name of Social Justice, allowed them to became more and more "progressive" with regards to merging Socialist/Marxist economic policies (authoritarianism) to make up for past social injustices... then they gave up on social tolerance as well. They demand you agree/conform with them on social issues as well: the opposite of liberty or tolerance. Thus, they became so focused on Social Justice, they became anti-liberal authoritarians to get it.|
|Am I a libertarian? - While I lean little-l libertarian, I'm not really a real Libertarian (or that's what they tell me). I'm for less government (especially federal), for more isolationism and less militarism, and for more individual liberty and property rights and so on -- all things that align well with Libertarianism. But I also believe things that contradict most people that call themselves Libertarian (though isn't a requirement of the dogma, seems to be canon, for most). Things like I believe that society has a speed limit on change, or you get instability -- so not only which direction you go, but how quickly matters. I'm for some military intervention, I believe in fair trade over free trade (the market will work out free trade in long run, but in the short run people get hurt -- so you need limits), I'm for some social services (just less), and believe that most things (like the legalization of drugs) must come very slowly and with education or there will be backlash. Thus, I call myself more a conservatarian -- conservative on how quickly I'd want libertarianism, and conservative on how far down that path I'd go.|
|Big-L versus Little-l - One quick aside, libertarianism (with a little-l) is a philosophy or belief system, with many branches, while big-L Libertarian is a political party. Just like Republicans and Democrats, no two Libertarians can seem to agree on what the priorities should be, and how to implement every tenet of their philosophy. Since quirks of our language allow for mis-capitalization, a lot use big-L when talking about little-l, so it always helps to clarify whether someone who says libertarian means philosophy or party.|
|Frederick Hayek - Friedrich August von Hayek (1899.05.08 – 1992.03.23) was an Anglo-Austrian economist and philosopher best known for his defense of classical liberalism. Hayek shared the 1974 Nobel Economic Prize with Gunnar Myrdal for his "pioneering work in the theory of money and economic fluctuations and [...] penetrating analysis of the interdependence of economic, social and institutional phenomena". Blah blah, he showed why Socialism fails: the dispersed knowledge problem -- that the people on the bottom know more than the people on the top about the specifics of issues, so the more you have to push up the chain for decision making, the more errors and delays will be introduced.|
|Left Libertarian - Left-Libertarian is an oxymoron, like kind rapist or practicing compassionate gennoacide. You are either trying to increase individual liberty (and accountability) and are on the libertarian spectrum, or you're trying to seize the means of production and force social equality through government force, but not both. You can't pretend to be about individualism, then say that's why you want to use the state to force collective values. So anyone that says Left-Libertarian without openly mocking the hypocrisy of it, lets you know that they're just a Social Justice Warrior trying to wear the costume of a freedom loving person, but they aren't.|
| Libertarian Joke -
|Libertarians are anarchists - There is a reductio ad absurdum argument by the left, that Libertarians are all anarchists, or it would lead to anarchy. This is like saying anyone for a single social program wants complete Authoritarian Marxist Tyranny. There might be a few that far out on the bell curve, but they're not the norm of the movement, nor close. This also devolves into idiotry about "who would build the roads, schools, police". We had all of those back before we had an IRS and were far more Libertarian than most Libertarians today would want -- so it's an argument that appeals to the ignorant or partisan, not the informed. We can debate how extreme a Libertarian is, and whether they are an anarchist in Libertarian clothing (and there are a handful out there). But saying Libertarians are anarchists is like calling all Democrats rapists, just because Bill Clinton was one.|
|Roads and Infrastructure - Many view the United States as a free market capitalist state and Nordic countries such as Sweden and Finland as socialist due to their extensive welfare system. Yet, in the United States, most roads, highways, and other transportation infrastructure are publicly owned and operated. Meanwhile, the vast majority of roads in Sweden and Finland are operated by the private sector and maintained by local communities. The Norwegian model works better and costs half as much. In the U.S. it also helps to remember that the vast majority of roads were created before the federal government got involved in national highways, and they worked just fine... often better, and definitely much cheaper and with more local control and less waste.|