Tonight is the night of the full moon. This will be the second full moon of the month, also known as a blue moon. Contrary to some rumors, the full moon tonight won't be blue, but rather it will glow yellow like it always does. Moonlight is a result of the moon reflecting the suns light back to earth like a mirror. Of course the moon doesn't produce its own light and it certainly doesn't produce blue light! That being said, go out under the full moon in the middle of the night or early morning hours and you might find there does seem to be a bit of bluish light cast over the landscape.
The term "blue moon" apparently was in use at least by 1937, when it was used in the Maine Farmers Almanac in reference to the third full moon in a season. The popular changeover to blue moon referring to the second full moon in a month came from a 1946 Sky and Telescope article title "Once in a Blue Moon". The article interpreted the 1937 Maine Farmers Almanac use of "blue moon" as meaning the second full moon in a month.
Regardless of the origins of the term blue moon, the moon is indeed full tonight, so take advantage of its wonderful evening light to enjoy the nightime outdoors under its soft glow.