What causes a lunar eclipse?

Related questions

• How often does each location on Earth experience a total solar eclipse?
• What is the only phase of the moon during which a solar eclipse can occur? Why?
• What is a penumbral eclipse?
• What is happening when the phases of the moon are waxing?
• What is syzygy?
• What is a spring tide and what causes this phenomenon?
• What is an umbra?
• What causes a solar eclipse?
• What are the conditions under which an eclipse (both solar and lunar) will occur?
• What causes spring and neap tides?