Message to a heedless world: Please remember that the O in the formula H2O is a capital O meaning oxygen, not a zero meaning zero. Water is composed of hydrogen and oxygen, not hydrogen and nothing.
Heedless world replies: Get a life, man.
Heedless world continues (after some thought): How do you know the difference anyway?
Me: Zeros are narrower.
Heedless world: This is truly sad.