高度是以坐标系为基准，在地球表面定义向上为正，度量由下往上的距离。 图形或物体之高，指的是垂直于底面到上顶点之高度之距离。 三角形有3条高，分别从3个顶点垂直到底边。 高不一定在三角形内部，钝角三角形的高则有2条在三角形的外部。

Height is the measure of vertical distance, but has two meanings in common use. It can either indicate how "tall" something is, or how "high up" it is. For example "The height of the building is 50 m" or "The height of the airplane is 10,000 m". 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.