What's the difference between a new moon and a full moon in terms of their appearance and visibility in the night sky?

Oh, darling, a new moon is like a shy debutante, hiding in the shadows with barely a peek of light, while a full moon is out there strutting its stuff, all big and bright for the whole world to see. It's like a lunar glow-up, from subtle to spectacular, on the celestial catwalk of the night sky.