What is the difference between analog and digital information?

I already understand how digital systems use discontinuous values (like how binary systems are based on variables that allow only two possible conditions: 0 or 1), and how analog systems use continuous values like an arbitrary range of voltage inputs. I'm just trying to understand it more clearly using examples from daily life. For example, why is an analog clock "analog" and why is a digital clock "digital"? How are you supposed to know what variables to look at when catagorising something as analog or digital? Thanks.|||Digital is discreet, analog is variable|||yep