Dear alls, I've got a autolisp program from someone,and I trying to interpreting it,I do know is it true or false,can somebody to comment it. And then did not know why it program must be added 1.(setvar "attdia" 0) 2.(setvar "blipmode" 0) 3.(setvar "blipmode" 1) 4.(setq 11 nil ur nil x1 nil.................lr nil) If we create a program without no.2 & no.3 it program can run too,any comment it. Thanks for your comment Best regards Ade Suharna