In the Chinese language, “低” and “高” is a pair of antonym which mean “low” and “high” respectively. And “调” means “tune, tone” and so on. So you know that “低调dīdiào” means “low-key” and “高调gāo diào” is the opposite. Chinese people advocate that people should be modest and calm, so when they remind people or themselves, they just say “we should 低调”.

And when you are really going to do something, you should be active and hard-working and embody a sense of long-term plan, i.e. 高调. They can function as adjectives. And many people think that we should “低调 when you interact with other people; but 高调 when you are doing your work.” They are quite popular among the young people who always like to produce and use humorous and individual words.