* The moon doesn't produce its own light. It shines because sunlight reflects off its surface.

* The sun is so bright that it usually overwhelms the moon's reflected light at night, making it appear fainter.

* During the day, the sun is still shining. Even though the sun is high in the sky, the moon can still be in a position to receive sunlight and reflect it back to Earth.

* The phase of the moon matters. A thin crescent moon or a waxing/waning gibbous moon is easier to spot during the day because it's less illuminated than a full moon.

Think of it like this: Imagine you're standing in a brightly lit room. It's harder to see a dim light bulb, but if you hold a mirror up to that same light bulb, you can see the reflection clearly. The moon is like that mirror, reflecting sunlight even during the day.