What is Life?

What is Life?

Life can be happy or sad but what is it really? The boundary between living and dead has long been a subjective argument of mankind. If it grows, is it alive? Ice and rust grow but are not considered alive. If it moves, is it alive? Water and air move, some plants and animals do not. Right now, the common factor within all things considered alive is DNA. Some viruses exist which contain only RNA - are they alive? [NS] {NR}