SIGN

[ccamilalvarezz]

Hi! When I stand on any line a sign appears. I don´t know what it means and why it appears. I want to remove it. Does someone knows how? Thank you! 

[pendean]

This perhaps (hard to tell from your screenshot) https://knowledge.autodesk.com/support/autocad/learn-explore/caas/CloudHelp/cloudhelp/2019/ENU/AutoC...

[David_W_Koch]

That symbol indicates that there is a constraint between those two lines, constraining the horizontal line to be perpendicular to the vertical line.

If you do not want that constraint to be applied, you can use the DELCON command, selecting all objects from which you wish to remove the constraints.

If you did not intend for there to be a constraint there, and do not want new constraints to be inferred as you add new objects, set CONSTRAINTINFER to 0.