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    A rainbow is an optical and metereological phenomenon. It is caused by both reflection and refraction of light in water droplets, resulting in a spectrum of light appearing in the sky. It takes the form of multicoloured arch. Rainbows are caused by the sunlight which shines through raindrops, and they usually appear in the section of the sky directly opposite the sun. Rainbows can be seen only when the sun shines on the drops from behind the viewer. They can also occur in the mist of waterfall and in the spray of a garden house. Rainbows can be full circles. However, the average observer sees only an arch, formed by illuminated droplets above the ground. The colours of a rainbow are red, orange, yellow, green, blue, indigo, and violet.

When can we see a rainbow?

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