Every people has its own way of saying things, its own special expressions. Many everyday American expressions are based on colors.
Red is a hot color; Americans often use it to express heat.
They may say they are red-hot about something unfair, when they are red-hot they are very angry about something.
The small hot tasting peppers found in many Mexican foods are called Red Hots for the color and their fiery taste.
Fast loud music is popular with many people. They may say the music is red hot. Especially the kind called Dixieland Jazz.
Pink is a lighter kind of red. People sometimes say they are in the pink when they are in good health.
The expression was first used in America at the beginning of the 20th century.
It probably comes from the fact that many babies are born with a nice pink color that shows that they are in good health.
