Your camera’s shutter speed allows you to FREEZE images by using a faster shutter speed or BLUR images by using a slower shutter speed. A slow shutter speed means leaving the shutter open for longer amounts of time and fast shutter speed means leaving the shutter open for shorter lengths of time.
- 1 second = slow shutter speed (a long length of time)
- .0008 second = fast shutter speed (a short length of time)
You may want to show that an object is in motion and have it blur just a tad (a common practice for waterfalls) or you may want to freeze an object in motion so that all the details are kept sharp (such as in photographing sports). Either way, the key to freezing or blurring a moving object in a photograph is shutter speed.
Use a fast shutter speed for sports - Shutter Speed .0008 s
Use slow shutter speeds to capture motion - Shutter Speed .0667 s
I won’t get too technically (because basically I can’t) but shutter speed is the length of time the camera’s shutter is open. While the shutter is open, light is being recorded and the image is being “taken” so to speak. 
So, the longer the shutter is open, the more movement is captured and the blurrier moving objects will be. This effect is used quite artistically with lights and moving water.
So, the assignment for this post is to experiment with shutter speed. Here’s what to do:
- Set your camera to Shutter Speed Priority mode. This is denoted by an S on the dial on my Nikon D5000. Tip: If you’d like to know a good place to start with the shutter speed, take a picture in auto mode first and take note of the shutter speed used. Go up and down from that in the next steps.
- Take a few shots of the moving object with slow shutter speeds and look how the image blurs. Tip: Use a tripod. Any movement causes blur, movement by the object or movement by your camera. So, be sure to keep the camera extremely still when using slow shutter speeds.
- Take a few shots of the moving object with fast shutter speeds and see how the image freezes (or at least freezes as compared to what blurred looked like).
Share your experiment here! Feel free to get way more creative than using the ceiling fan. Lights and water are both fun to work with when experimenting with shutter speed.
Here are my fine examples of the moving ceiling fan blades in my living room.
Here’s PROOF that I’m new to photography: Aperture is spelled WITHOUT the second A! 
The first picture of the series with the blades blurred the most has the slowest shutter speed (the shutter stayed open the longest length of time). The last picture of the series where you can clearly count there are five blades has the fastest shutter speed (the shutter stayed oped the shortest length of time).
If you don’t know what the Aperture and ISO mean in the image, don’t worry. We’ll cover those two topics very soon! For now, just focus on learning what shutter speed is, what it does, and how you can control it to get the results you want (frozen or blurred action).