The Moon's Shadow
If you want to see a solar eclipse, you must be in the path of the Moon's shadow, which has 3 distinct parts:
Umbra: The innermost and darkest part of the Moon's shadow. The Sun's light is blocked in places on Earth where the umbra falls. The Sun's disc is not visible anymore.
Penumbra: The outermost and the lightest part of the Moon's shadow. Only part of the Sun's light is blocked in places on Earth where the Moon's penumbra falls. The Sun's disc is partly visible.
Antumbra: The Moon's antumbra lies beyond the umbra. It appears with the growing distance from the Moon. From Earth, the Moon appears smaller and cannot completely block the Sun, so the Sun's outer rim is still seen.