The term conservative is derived from the word conserve. The idea in politics and society in generals is to conserve those elements which have stood the test of time and experience. These are referred to as traditions. Such things as the nuclear family, free markets, private property, meritocracy and the rule of law.

Liberal is derived from the Latin 'Liber' and essentially means free. The idea in politics and society in general is to remove the constraints on men which prevent them from being free.

Personally, I think these two viewpoints are compatible if rightly understood.