Converts 2D polylines between the "legacy" heavy and optimized lightweight formats.
  The following prompts are displayed.
  
  - Enter polyline conversion option
		
 
-  Specifies the format to which 2D polylines are to be converted:
		  
- Heavy - Converts lightweight polylines to "legacy" 2D polylines, which contain additional information in the form of vertex objects that increase drawing file size and reduce performance.
			 
 
- Light - Converts "legacy" 2D polylines to lightweight polylines, which are optimized objects that reduce drawing file size and improve performance.
			 
 
		 
  Note:  
	 -  By default, the 
		  PLINETYPE system variable specifies that "legacy" 2D polylines should be updated automatically to lightweight polylines when you open a drawing.
		
 
-  The 
		  CONVERT command can be used to update "legacy" hatches and 2D polylines primarily created in product releases prior to AutoCAD Release 14 or AutoCAD LT 97.