本标准的主要目的是为公司之间的交换定义2D CAD文件结构的通用格式。2D CAD格式被理解为Bentley MicroStation DGN和Autodesk AutoCAD DWG格式。

The primary purpose of the standard is to define a common format for 2D CAD file structure for exchange between companies. 2D CAD format is understood as Bentley MicroStation DGN and Autodesk AutoCAD DWG formats.