Growing up as a kid, I was always told to look both ways before crossing the road. Turn left, turn right, double check my left and make my way across the road.
The main muscle that allows us to rotate our head is the sternocleidomastoid (SCM) which is shown in the picture. This muscle is innervated by the Accessory Nerve (Cranial Nerve XI). Our SCM also allows us to tilt our heads.
Along with supplying the SCM, the Accessory Nerve also supplies our trapezius muscles. Our trapezius muscles allow us to shrug our shoulders. Both of these muscles are tested on examination to check your Accessory Nerve.
Now when you cross the road, you can thank your Accessory Nerve.