Newbie here. Why are blue paths showing up next to paths I created?
Hi! I'm following a Lynda.com tutorial, and trying to figure out what causes these blue paths, which I didn't create (on purpose), to show up next to paths I did create.
Right before this screenshot, I used the Selection tool and made a marque box to select the [orange anchors]. Once I did that, the blue vertical paths appear, which didn't happen in the instructors video (He is using a slightly older version of AI).

Then as instructed I join the paths I get:

Instead of what the instructor gets (video screenshot), which is:

I can manually delete the blue lines, but I'd like to understand what the issue or settings problem is so I avoid this in the future. Thanks!
