How does light travel?
Light travels directly. This is why shadows are formed. If light could move freely, it could easily travel behind shadow-producing objects. The image on the top left shows the Sun, the Moon and the Earth. The shadow produced by the Moon has produced a solar eclipse. This means that the Sun is completely blocked out in certain places on the Earth.
The image on the bottom left shows the Sun, the Earth and the Moon. If you were to look at the Sun from the Moon, you would see that it is blocked by the Sun. In other words, the Moon has ended up in Earth's shadow. This has produced a lunar eclipse.