The origins of the Scapular is the Monastic Scapular, a wide strip of cloth that goes over the head, and hangs in front and behind the habit. It probably had it’s origins as an apron to keep the habit, or clothing clean when one was working.
There are many different scapulars, (Something Ron probably did not know) While the Scapular is not a requirement in Catholic life, it is a source of graces, and a reminder of our individual resolve to live a Christian life. This Catholic Encyclopedia article goes into greater detail.