Height is the measurement of vertical istance, but has two meanings in common use. It can either indicate how "tall" something is, or how "high up" it is. For example one could say "That is a tall building", or "That airplane is high up in the sky". These can both be referred to as the height of the object, as in "The height of the building is 50m" or "The height of the airplane is 10 000m". When used to describe how high something like an airplane or mountain peak is from sea level, height is more often called altitude. Height is measured along the vertical (y) axis between a specified point and another point.