It's called the Rule of Thirds; I learned this one while studying photography, painting, AND design while in college. The deal is you divide your image into nine sections by two equally-spaced horizontal and vertical lines. Those four lines should ideally correlate to important features within your photograph. Additionally, the four intersections created these line can highlight features of your image. This is a very simple method of increasing visual interest in your subject.
Here is an example of a cute picture of The Cutest Puppy Ever where I didn't employ the technique (he's still adorable!):
So I've taken a step forward, flipped it vertically, turned on my flash, and employed the rule of thirds...here's the result:
I'd like to illustrate further what I mean by The Rule of Thirds; if you're like me, my above description won't hold a candle to this: Now does,
The deal is you divide your image into nine sections by two equally-spaced horizontal and vertical lines. Those four lines should ideally correlate to important features within your photograph. Additionally, the four intersections created these line can highlight features of your image.make more sense? There are two lines that run across the image, and two that run up and down. If you are taking a picture with a horizon line, or a table line, or any horizontal line...if you place that line on one of those two guidelines you're pretty much sure of a good shot. Similarly, if you are taking pictures of a cliff, or a building, or people in front of a cliff or building, place those big details on the guidelines.
In this image, I wasn't working with architectural or geographical landmarks, but those far closer to home. The rules work there as well. The pillow functioned as horizontal lines, and The Cutest Puppy Ever provided vertical. Better yet, his cute little button nose (!) fell right into one of the intersections, which makes for an even stronger composition as it gives your eye a natural place to rest.
No worries, the Rule of Thirds is a forgiving rule. You don't need to be exact; more than anything you need to avoid placing horizontal and vertical lines in dead center of your photograph...while that might be the obvious composition and is perfectly fine, it won't be the extraordinary photograph you are striving towards!
Mostly, enjoy taking those photos of your beautiful subjects! Snap away and don't be afraid to be creative...you'll be amazed at the amazing photographs you'll take!