Orthogonality is the property that means "Changing A does not change B". An example of an orthogonal system would be a radio, where changing the station does not change the volume and vice-versa.
A non-orthogonal system would be like a helicopter where changing the speed can change the direction.
In programming languages this means that when you execute an instruction, nothing but that instruction happens (very important for debugging).
There is also a specific meaning when referring to instruction sets.
与恶龙缠斗过久,自身亦成为恶龙；凝视深渊过久,深渊将回以凝视…
