Rule of thirds.

 Rule of Thirds

 The rule of thirds is a technique applicable to any form of photography, used to make images more appealing. The rule of thirds separates elements in a composition into thirds. 

 When a key element in an image is placed underneath the points where the lines cross, the subject instantly has more impact. Your eyes are drawn subconsciously to these points. The lines themselves are the second strongest focal point in an image. 

L ike this bottle. If the bottle was in the middle of the photograph, it would have much less impact. But placing the bottle  on one of the rule of thirds grid corners, the image becomes more interesting and the bottle has more impact.

Here is the grid used to place the subject. As you can see the bottle is directly underneath the bottom left corner of the rule of thirds grid.