Briefly describe what four thirds digital photography is about?

Answer 1

Sorry to give the first two answers a thumbs down, but they are confused with 'the rule of thirds'.
The four thirds system was devised by Olympus and Kodak and it has to do with the physical size of the sensor... "4/3 inch".
For more information, here's an in-depth description: http://en.wikipedia.org/wiki/Four_Thirds_System

Answer 2

Basically when you take a photo your subject is not in the middle of the frame. But is either in one of 4 areas of the screen making the image to be more easier to look at. Rule of thirds: top right or bottom right corner, and or top left or bottom left corner. Look at any professional photograph and you'll see what I'm talking about. Hope this helps!

Answer 3

Basically, it's about good composition- where important elements of your photograph are located to make it pleasing to the eye.

You mentally divide the viewfinder area into thirds by drawing imaginary lines, both horizontally and vertically. By placing important elements of your photograph at one or more of the four spots where those lines intersect, you get more interesting photos. Happy shooting!