shutterspeeds

When we press the shutter of a camera we hear a click, that's the SHUTTER firing.

Without getting too technical, the SHUTTER SPEED is the length of time that the shutter is open.

The top picture is of a wave frozen as it curls. This picture was made using a fast shutter speed, in fact it was about one thousandth of a second.
The camera was deliberately set to this speed in order to catch this exact moment.

The bottom picture is of a Tram, taken at night, with a slow (or long) shutter speed.
As you can see, the movement of the Tram has been accentuated by using a shutter speed of around one eighth of a second.