Freezing Motion can be incredibly useful in photography because it will allow you to create images that the human eye cannot. By utilizing shutter speed, cameras can freeze a tiny moment in time perfectly.
Freezing Motion in Natural Light
Close your eyes, blink quickly, and close them again.You will see an flash of an image, but only for a moment. In a nutshell, shutter speed works the same way your eyes do. You can control how long the shutter stays open, which dictates what that image will look like.
Long shutter speeds = Motion Blur
Short shutter speed = no Motion Blur
What your shutter speed will be has everything to do with what you are photographing. Slow moving subjects will not need as much of an intense shutter speed to catch them in Motion. Fast moving subjects, however, will.
Be aware that you must have enough available Light to shoot with a fast shutter speed! If you crank up the speed but don’t change anything else, you will likely get a very dark and underexposed image.
Fast shutter speed = Less Light enters the camera
The easiest way to shoot fast moving objects is in Shutter Speed Priority Mode. In this mode, the aperture and ISO are chosen according to what the shutter speed needs to be. As long as you are okay with being flexible in those areas, this is a great option for shooting.
Canon = TV
Nikon = S
Here is a chart to help with visualizing the Difference between slow and fast shutter speeds. As you can see, a slow speed like 1/60 will allow for plenty of motion blur. A speed like 1/2000, however, is very fast and will freeze even the fastest cheetah.