Different countries have different definitions of left and right. There seems to be some system, but also... well, let me give you an example: In Slovakia, the political party promoting marijuana legalization and homosexual marriage was labeled by its opponents as right-wing, because... well, they also supported free-market, and supporting free market means opposing communists, and since communists are left-wing, then logically if you oppose them, you must be right-wing. Having exactly the same opinions in USA would make one left-wing, if I understand it correctly.

This said, the examples I have in mind may be rather atypical for most LW readers. Thinking about my country, I would roughly classify political parties into three groups, listed from most powerful to least powerful.

1) Communists, including some small Nazi-ish parties, because they have a similar ideology (defend the working class, blame evil people for everything bad; the difference is that for Communists the evil people are Americans and entrepreneurs, while for Nazis they are Americans, Hungarians, Jews, and Gypsies; also both are strongly pro-Russia).

2) Liberals/Libertarians, basicly anyone who knows Economics 101 and wants to have some free market, and in extreme cases even things like marijuana and gay marriage.

3) Catholics, who only care about more power and money to Catholic church, and are willing to support either of the previous two groups if they in return give them what they want (so far they mostly joined the Liberals, but it always created a lot of tension within the government)

So for me, "left-wing" usually means (1), and "right-wing" usually means (2) + (3).

In my country, knowing Economics 101 already gets you labeled "right-wing", and if you say things like "if you increases taxes, you will punish the rich, but you will also make stuff more expensive for the poor" or "if you increase minimum wage, some people will get higher salary, but other people will get fired or unable to find a job", this is perceived by many as being mind-killed.

But in other countries it may be completely different.