Shutter speed is used to allow moving images look still and is the effective length of time a camera's shutter is open. Slow shutter speed is used so part of the photography is blurry, adding the effect that it is moving. Fast shutter speed does the opposite of this and freezes the movement so it shows in the photograph. The top two photos show fast shutter speed where the shutter is open for 1/800th of a second and the bottom two photographs show slow shutter speed where the shutter is open for 1/500th of a second. The only possible problems with the top two photographs is the poor framing, as half of the bodies and hands are cut out. A solution to solve this is to take my time when taking the photograph and to review them as soon as you have taken them. The problems with the bottom two is that they are slightly out of focus and a way to solve this is to put your camera into automatic focus mode. My targets for the next time I take photographs would be to review my images as soon as I have taken them experiment with shutter speed more and get them more accurate.