【求助】ABS和WCS的区别

云淡风清

help里面是这样解释的：
The Absolute Coordinate System (ABS CSYS) is the coordinate system from which all objects are ultimately referenced. As an example, all data for points use this coordinate system. The Work Coordinate System (WCS) is used in determining orientations and angles. This combination of using both coordinate systems is called the CONSTRUCTION SPACE in Open C API. As an example when creating an arc, the center, orientations and angles are determined from the WCS.  
不过看完之后还是有些稀里糊涂的
大家能不能谈谈对此的理解？望指教，谢谢！

goodluckwu