For today's topic I will explain what shutter speed is. This one goes out to Hariz :D Okay so what a shutter speed does is control how fast the shutter opens and closes to reveal light to the camera sensor. The faster the shutter speed, the less light reaches the sensor which also means less time for the camera's sensor to collect all the light data.
There's not really a definite rule to follow, because photography is a very subjective thing and it's up to you how you want to present your vision. But the basics are, faster shutter speeds are used to freeze action. You will get sharper pictures too. For this to be in effect you should generally use nothing less than 1/500s for best effect. But the downside is that you will only be able to do this in very brightly lit environments. You could counter this by using flash or multiple flashes. But that's another topic entirely.
So here's an example of an action-freezing shot. Shot on ISO 200 at 1/800s under the midday sun at f/5. Apertures also play an important role in your photos. But I will explain this at another time. So as you can see I froze this quite nicely. Everything is clear and no motion blurs.
Next off!! Low shutter speeds. Low shutter speeds are usually used for low light photography or for more artistic approaches. There are a lot of things you can do with long exposures. Light painting, light trails, motion blure, etc. But basically its used for low light shots. Here's an example of one. Shot on ISO 200 and 3 second exposure time at f/4.5. Make sure you have a tripod on for these kinds of shots.
And now I'll show you a creative way to use a low shutter speed. I took this at ISO 800 and at the shutter speed of 1/20s to get more of the background in since it's pretty dark and have some light trails by swaying the camera around as i press the shutter button, but at the same time freeze the action. So all I had to do was use my SB-600, set it on manual, around 1/16 if I remember correctly and set at a zoom of 85mm.
So that's it from me. :P If you're ever in a bind you can always google it. But if you can't find what you're looking for you can ask me. I'd be happy to help. :)