Shutter Speed.

A picture is taken when the shutter opens and the image is exposed to light. Shutter speed is how fast the shutter opens and closes. Shutter speed is measured in fractions of a second, the larger the denominator the faster the shutter will open and close. As the shutter speed increases the amount of light getting to an image decreases. A shutter speed of 1/1000 is faster than 1\500, but only get half the amount of light. The shutter speed is affected by the aperture and the ISO setting. Using a high ISO setting or a Larger aperture will allow more light into the camera. This allows a faster shutter speed.

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