The document discusses the phases of the moon and how they appear from Earth. It explains that as the moon orbits Earth, different portions are illuminated by sunlight, causing it to appear to change shapes. There are 8 total phases as the illuminated portion waxes and wanes from new moon to full moon and back again over the course of around 29.5 days: 1) new moon, 2) waxing crescent, 3) first quarter, 4) waxing gibbous, 5) full moon, 6) waning gibbous, 7) last quarter, 8) waning crescent. Diagrams and descriptions are provided to illustrate each phase.