human
Explain the phenomenon of rainbows in the sky.
assistant
Rainbows are one of nature's most spectacular sights. They are created when sunlight passes through water droplets in the atmosphere. The water droplets act as a prism, refracting the light into the seven spectral colors of the rainbow – red, orange, yellow, green, blue, indigo, and violet. Depending on the time of day and the water droplets' size, rainbows may appear single or double, and they can even appear as a full circle sometimes. Rainbows are a beautiful reminder of our world's beauty and nature's magic.