The weird thing here in Australia is that the Liberal Party (currently in power on the federal level) IS a conservative party๐๐
But generally i think conservatives are called that because they want to conserve the status quo in some way (usually in terms of who holds power within society). 'liberal' as i undertand the term is used politically in the US denotes those concerned with promoting social justice. needless to say then that conservatives and liberals will be in opposition to each other...
I'll try and make this as unbiased as possible, since it's hard to offer a defitinion objectively if one associates oneself with a particular camp.
A conservative viewpoint believes that things are good as they are, and that change will disrupt the status quo leading to a worse situation.
A liberal viewpoint believes that things are not as good as they can be, and that introducing change will improve upon the status quo.
-mike