A brief rough history, in case anyone is interested:
17th century: Kings and shit. The people supporting the rule of the king are in power. They become conservatives.
18th century: Liberals appear. They believe men have certain inherent rights from nature. They don't dig kings, but they do believe in private property. They sit to the left in parliaments, the conservatives sit to the right.
19th century: Marx gives us his take on history and labour. Liberalism is given a competing framework from the left.
20th century: All kinds of shit goes down, partly because the conservatives and the liberals are terrified of the Marxists and give the fascists the keys to the kingdom, partly because of a Marx-inspired Leninists take control in Russia. The "new" left (socialism) becomes a major force in the postwar era, promising to build a new world on the ashes of the old.
21st century: There seems to be a head on collision. People feel strongly about these concepts, but it seems many have forgotten where they come from or what they mean. Disinformation campaigns have gotten efficient. Green politics enter the field.