Shampoo

I've always wondered what shampoo is. How is it different from body wash? In fact, how are shampoo and body wash different from hand soap (or even detergent)?

If I bother to look it up or talk to people who have studied the subject, there's probably a world of difference, but I'll save that for another time... the more important question at hand is this: should I be using shampoo on my body?

I mean, as a post-puberty human, my head is not the only place that has hair. Given, most of the rest of my body is more skin than hair (an unfortunate fact when I see how comfortable dogs or cats or stuffed animals look on a winter day), but there are several places where hair is dense enough to warrant the question: why am I not using shampoo there?

This scenario has probably never happened to you, but it happens on the rare occasions and, when it does, it is overly embarrassing: let's say you are talking to someone at your desk and you suddenly notice a hair in a noticeable location, let's say, the table, and you will not be able to remove it without drawing attention to it. This hair in question matches your hair colour exactly but no one else in the vicinity has the same hair colour as you. That, on its own is nothing that uncommon and nothing to be too alarmed about. But what if that hair is obviously not from your head?

See, this scenario is only a problem because it is so obvious when hair is not from your head but from elsewhere on the body. Why is it so easy to tell when hair is not from your head? If I start using shampoo and conditioner on other areas of my body with dense hair, would this difference become less noticeable?

One has to wonder.