Coloring Books

There is a definite Fervent Fever for Coloring books - not the kind that my kids had when they were in grade schools.
This is much more sophisticated.

There are the ones with flowers, 
                the ones with animals, 
                the ones with buildings, 
                the ones with landscapes, 
                the ones with people, 
                the ones with symbols, 
                the ones with abstract forms, 
                and so on.  

My neighbor, a retired educator, received such a coloring book with a set of colored pencils, from her sister. I suppose her sister thought that she needed such activities to occupy her time now that she is no longer working. Truth be told, I think my neighbor is now busier than ever, doing a lot of things. 
I am not saying that she did not like her job. She definitely did. She was a very good teacher. But she has other interests as well. 
Now she has time to do the things that she had wanted to do but had not had time to do before retirement.

The last time I saw her, she told me that she had been too busy to have tried her hands at working on her Coloring Book yet.

I, myself, received a similar book from one of my daughters (Not with colored pencils, since she knows that I have plenty of them, as well as all different kinds of colored markers, colored brush pens, etc. After all, I have been painting and drawing for a number of years.) I did do a few sheets. 

Believe it or not, during Christmas time when my other children, in-laws, and grandchildren, came home, some of them tried their hands in doing some pages of My coloring book. 

Was I surprised? Yes and no.

One of them said that it was a challenge. 
Another said that it had a calming effect on him.
Mind you, these are not "kids".

So it was not a total surprise to me when I read that one of the big craft stores sold some 27 millions dollar's worth of Coloring Books and Related items this year. Wow!

In this day and age, when even the little ones are hooked on electronics, why is a simple coloring book became such a Draw? 
(No pun intended.)

Remember the hula-hoop?
You may be too young.
It was such a popular item - a simple plastic hoop - that took the world by Storm.  

But Coloring Books?

Would someone enlighten me as to Why?

Perhaps one of us may Reinvent the wheel again!