The answer ranges from standing out from the crowd to psychological theory
After making the jump from monochrome to colour, animators all over the world quickly fell in love with the colour yellow, ascribing it as the default design hue of countless characters. But why yellow?
According to the people over on YouTube’s ChannelFrederator, it’s down to a mixture of personal decisions, scientific and marketing research, and the colour of the sky.
There is no single answer, but several theories coming from psychology and communications theory offer some insight; one theory is based on the fact that televisions display light using the Red-Green-Blue scale, rather than the Red-Yellow-Blue one.
In the RGB model, yellow is a complementary colour to blue, meaning characters with yellow design features will stand out against blue skies or water.
When The Simpsons first premiered in 1989, Matt Groening crafted the Simpsons to have yellow skin so that they would be instantly recognisable to anyone channel surfing. The jaundiced skin tone of Homer and Marge was at odds with the peach-coloured skin prevalent in animation at the time, making the characters stand out from the crowd.
To learn more about why yellow is so common in cartoons, take a look at the video in full below: