OK, this is a lesson in shutter speed and how it relates to ISO and aperture for my new photographer friends.
Today was a very sunny day when I went to take my daily picture. I knew that because it was very bright out, I should put my ISO to 100, which is as low as it goes on my camera (on some cameras this goes lower). I wanted to use a wide open aperture (f2.8 on this lens) to get a bit of depth of field because I like that, but I knew that if it was too wide open it would make the picture too bright, blowing out the subject. So, I chose to use a very quick shutter speed so that the amount of time the camera was open to light would be very quick. I chose 1/1000 sec, which is really fast. As you can see, the picture still came out very bright, but not so bright that it blew out the flower, but there is still some blur on the mulch in the back of the flower.
I really like to use high shutter speeds when possible because it makes the pictures tack-sharp since it cuts down on the camera shake. Unfortunately, unless there is a lot of light, to get such high speeds I would have to up the ISO. Hope that helps a bit (P).