A zig-zag road marking has left the internet scratching their heads. While we all know our stop signs and double yellow lines, some of the more obscure road rules can slip through the cracks as the years since our driving theory tests add up.That's exactly why a bunch of people were confused when they found out what the squiggly road marking actually signifies.Those white zig-zag lines you spot daily at the roadside are easy to overlook if they don't seem immediately relevant to you.