Over exposure occurs when the shutter speed is to long, the aperture is to wide and letting in to much light and the IOS is to sensitive to light. This causes the image to be to bright and loses what your taking a photo of to the light.
Under exposure can occur if your shutter speed is to quick, the aperture isn't taking in enough light or the IOS isn't sensitive to the light. Under exposure is when the image doesn’t have enough light and is dark and very unclear. The only real thing you can see is the brightest parts of photograph because its trying to take in as much light as it can as fast as possible.
If your trying to take a photo graph of sports you will have to have a really fast shutter speed so nothing is caught with motion blur and take in as much light as possible because it wont have much time to take in light. So you would keep a wide aperture so you keep the focus on what your taking a photo of and take in lots of light. Also have a mid IOS to compensate how much light is coming in such a quick time. Also so you don’t get to noise.
Composition is the placement of whatever your taking a photo of in the shot and how the shot makes you focus on what your taking a picture of. I will be looking at 3 examples. The rule of thirds, leading shots and framing shots.
Rule of Thirds
The rule of thirds is a way of lining up you images so they look good and professional. The way it works is the frame or the shot is split into 3 sections across and down, anywhere the sections cross are fitting
Leading shots are when you take a photograph on something which draws your eyes to a main focus. For example if have a picture if a costal walk with a bar leading towards a shop. The shop would be the main focus and the bar would draw your eyes to that.
Framing shots are when you take a photo of something but have things sectioning out that main focus. For example if you take a photo of a sunset through a window, the window acts like a frame for the main focus which is the sun set.