Crescent, waning
The sun is always shining at the moon. However, sometimes we can only see part of the moon that the sun is shining on. When the sun is behind us and the moon in front of us, we can see all of the part of the moon that the sun is shining on. If the sun is behind us and the moon is to the left or right of us, we can see part of the moon that the sun is shining on and part that it isn't shining on. However, because that part of the moon is so dark, we cant really see it all, so we see a half moon. As the moon orbits the Earth wee see more or less part of it lit up. The moon then seems to disappear altogether, which is because we can't see any part of the moon being lit up. The moon is getting fuller at present, so each night we see a bit more of it lit up. After it is full we will begin to see less of it being lit up.
After a full moon as we see less and less it's called a waning moon
After the full moon, we see less and less of the sunlit side.
If a lunar eclipse is in progress, the moon is in the earth's shadow. If any part of the moon becomes almost as dark as the space around it, then that part of the moon is in the umbra of the shadow. If you can see the lunar eclipse, then you are on the night side of the earth. I guess that means you're also in the umbra of the shadow, because you can't see the sun at all.
After a waning moon one gets a new moon.
The sun reflects light off the moon at all times. The moon is always revolving, so eventually you see less and less until you see nothing. When you don't see the moon, its called a new moon.
You can see the moon when it is not full. The sun lights up part of the moon, but if you look carefully when the moon is not full, you can see the darker parts. This is easier when only a small part of the moon appears to be lit, as a brighter moon glares out the darker part making it harder to see.
When the moon is bright, the sunlit part of the moon that we can see is getting larger. When the moon is dark the sunlit part of the moon that we see is getting smaller.
Crescent is the phase that's less than half. Gibbous is the phase that's more than half, but less than full.
We see the Moon from different angles. When the Moon is opposite to the Sun in the sky, we see the illuminated part. When the Moon is in front of the Sun, we see the dark part. At a 90 degree angle, we see half of the Moon illuminated, and half dark.
The most important thing to know about moon phases is that the moon does not produce it's own light - it reflects the sun's light to the Earth. The moon orbits the Earth, so it's position with respect to the Earth and Sun change throughout a month. When the moon is in the same direction as the sun (when viewed from Earth), it cannot be seen as this is called the New Moon. As it orbits the Earth, in a few days we start to see a thin crescent and after a week has passed, we can see one half of the moon's lighted side. After another week, the moon is on the opposite side of Earth as the sun and we can see all of the moon's sunlit side (this is called the Full Moon). After another week we see less of the moon's lighted side and we see a half moon again (except the opposite side of the moon is lit up). We see even less of the moon (it becomes a crescent again) and it eventually becomes a New Moon again. This cycle repeats itself every 29 days or so.
whichever part you see