As the Moon revolves around the Earth it will go through phases depending on the relative locations of the Earth and the Sun. When the Moon is between the Earth and the Sun it will appear black and that is called a New Moon. When the Moon moves to the other side of the Earth it appears as a full Moon, totally illuminated by the Sun.
The Phases of the Moon
The Moon Phase is sometimes important in a spell. Typically, based on the purpose of your spell, you will want to perform your spell or ritual during a certain phase.
New Moon - Great phase for starting something new.
Waxing Phases - Great for improving something you already have.
Full Moon - The best time for fortune telling spells or skills.
Waning Phases - Bannishing spells or rituals to help cleansing are best cast now.
The Super Moon
Simply put, the Super Moon refers to a full moon which is larger than average. As the Moon revolves around the Earth it does not make a perfect circle. Instead it sometimes comes closer or moves further away from Earth. The closer it is to Earth, the larger it will appear in the sky. If the Full Moon happens when it is closer than it is 80% of the time, that Full Moon is called a Super Moon.
The larger, brighter Moon can have an effect on your rituals.
Charging Items by the Moon
Many magical items can be "charged" by the Moon. There are many ways to charge items, but using Moon light or Starlight are some of the most common and preferred ways. Simply leave the item someplace where the Moon light will shine on it overnight. This will charge the item. Doing so during a Full Moon or even a Super Moon will charge the item faster and more fully.