Here's an easy way to remember the rainbow colors and their order:

Just remember this: ROY G BIV.
The letters stand for the first letter of each color.
R is for red.
O is for orange.
Y is for yellow.
G is for green.
B is for blue.
I is for indigo.

V is for violet.


Rainbows appear in seven colors because water droplets break white sunlight into the seven colors of the spectrum (red, orange, yellow, green, blue, indigo, violet). You can only see a rainbow if the Sun is behind you and the rain in front.