When taking photos it is important to know what shutter speed to use to get the best effect or the most crisp image for what you are shooting. Shutter speed is the time in which the shutter of your camera opens and closes to allow light into the lens. For less blur in the image you typically will go with a fast shutter speed. This will capture a solid image and show what was happening at that snapshot in time. To show movement or blur you will typically go with a longer shutter speed. This will blur or mostly remove things that moved in front of the camera at that time. You can see images like this taken over highways with blurs of lights going up and down either side of the road. This is due to the movement and exposure of the lens
Below are some images with captions showcasing different shutter speeds and what happened as a result
This photo is an example of an automatic shutter speed. Not extremely fast providing a crisp image, but is a solid image will small amounts of blur. Higher shutter speeds are better for capturing moving images
This image here is using a lower shutter speed with a moving subject(shoe) The image does not look like it has nay action, it just looks poor quality but that is because this is not the type of photo you would use this for
Here is the same photo as above, but this one has a much higher shutter speed. This photo is much cleaner and clear to see. It may not be an exiting subject, but it is a better shutter speed for this photo. It allowed less room for movement so the shoe is not blurred because the photo was taken faster
The image above was used with a faster shutter speed. In this instance the speed would not matter as much because the subject is stationary. He can not keep perfectly still so a slow shutter speed will still show some blur from movement. In this case a faster shutter speed is better but it does not need to be super fast like a 1/250 or 1/500 shutter.
To sum it ups, The image above could be in the range of 1/30 to 1/8. but when you get into the 1/2 or higher territory even with a photo that is stationary the subject will have small movements that can affect it. If you are shooting a completely in-animate object a slower speed is fine. As you begin to take pictures of moving subjects or action shots you want the highest possible shutter speed compatible with your ISO