Here's a site that explains body shape pretty well. The numbers on the chart are from a study that was conducted and it shows that alot of rectangles actually think they're hourglasses.
http://www.diet-blog.com/07/do_you_p...ure.php?page=3
My measurements are kind of hourglass and kind of pear. I use to def think I was an hourglass but now that I know that only 8% of the population is I'm not sure. My waist is currently about 9.5 inches less than my bust and about 11.5 inches less than my hips. My butt does affect that measurement alot though because it's huge! but I think (maybe) I am an hourglass because I store fat like an hourglass. Which means everywhere! I hate my upper arms. But I also lose evenly. I also have broad shoulders that balance out my hips.
My cousin is the perfect example of a pear, she is tiny up top and big from the belly button down (in relation to her top anyway) and the first place fat goes or leaves is her thighs.
My friend Lindsay is a good example of a rectangle. She does have a noticeable waist, it's just not really dramatic. She actually has a great body, really balanced. The main difference between rectangles and hourglasses is the size of the waist. Also, they store fat in their belly before other areas.