Is this normal for iPhone 5?

Whenever I take a picture on my iPhone 5 (vertically, not sideways/horizontally) the picture appears to have 2 black borders, one on the bottom and one on the top when I'm viewing the photo I just took. Does this happen to you as well? As far as I'm aware it's always been like that since I've started taking photos. But I always thought at first there never used to be two black borders appearing, maybe it's just me. I'm not sure. I'm not talking about while taking the picture, I'm talking about when viewing the image after you have captured a photo. When I view the photo I just captured I see a black border on the top and bottom, if I have taken the picture sideways then the black borders appear on the right and the left. Is this normal?

I'm an iOS Technical Advisor for Apple and I have to be honest, I have never had anyone ask me this question before.
The default aspect ratio of a photo taken by any iPhone is 2:3. That ratio does not fit the iphone 5's screen perfectly because it is a little longer than previous iphones. So the black border is the extra space that the photo does not fill up.without the black borders you would not be able to see the entire image… You can zoom in and fill the entire screen up but if you do you will cut off a little of the pictures