I'm not able to create a line in ArcGIS. I started an edit session and began with straight segment. All I want to do is draw a line out of three single points - lets say the coordinates for the points are (20,30 ; 50,30 ; 70,50). Every time I finish sketching, ArcGIS is creating a polygon instead of just creating a line without closing it.
You must chose a target polyline feature in order to build a line. When you create a new feature class for instance,in arcCatalog, right click > new feature class), the first form will allow you to select the type of entity (e.g. point, polyline or polygon). This can also be done with the tool "create feature class" where you must specify the geometry. for details about selecting your target feature class, please specify which arcGIS version you are working with. In short, it can be changed in the "editor toolbar" with version 9.x, or you have to select a "template" in version 10.x