If you have been taking photos for a while, you may have hear the term "rule of thirds".
It has to do the the positioning of the primary subject within a frame.
Most of us do "bulls-eye" shooting.
The primary subject is dead center.
The people with the artistic eye say this is wrong and therefore we have the rule of thirds.
Here are two links to a very quick course in the rule of thirds:
http://www.silverlight.co.uk/tutorials/compose_expose/thirds.html
http://www.wildthingsphoto.com/tips/composition/thirds.htm
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