In what language would you greet someone by saying Ni Hao?

Ni Hao is a very basic term in Chinese, which translates to "hello or hi", Chinese is a tonal language. This means that while the Words might be the same, the meaning is changed when they are said differently. Also, much like other languages some things are specific by gender, age, and/or familiarity. However, ni hai, can be used with or by, and to anyone, at any time of day.