A library of standard linetypes is provided in the acad.lin and acadiso.lin files. You can use the linetypes as they are, modify them, or create your own custom linetypes.
Linetypes are defined in one or more linetype definition files that have a .lin file extension.
Each linetype is defined on two lines in a linetype definition file. The first line contains the linetype name and an optional description. The second line is the code that defines the actual linetype pattern.
A complex linetype can contain embedded shapes that are saved in shape files. Complex linetypes can denote utilities, boundaries, contours, and so on.
