The moon's orbit is tilted 5 degrees, therefore when it orbits Earth, it rarely crosses in a perfect line with the Sun and Earth. Because of this, eclipses do not happen every month. The Umbra is the darkest part of the eclipse and is the part in a total eclipse. The penumbra is the lighter shadow on each side of the umbra and is a partial eclipse.
Solar Eclipse
"An eclipse of the Sun". This occurs when the moon passes directly between the Sun and the Earth, casting a shadow on a small area of Earth. A total solar eclipse is the only time the corona is visible because the photosphere is blocked. This will happen during a NEW MOON.
Lunar Eclipse
"An eclipse of the Moon". This occurs when the Earth passes directly between the Sun and the Moon casting a shadow on the Moon. The shadow has a reddish tint from the sunlight bending around the Earth. These will typically last longer than solar eclipses and be more visible around Earth because the Moon is much smaller then Earth. This will happen during a FULL MOON.