Short lesson- there are only three variables to taking a picture really. Each one of them influences the light coming through an opening to get the correct exposure. ISO- Think of this sort of like film speed. The lower the number is, the less sensitive the sensor is. The less sensitive it is, there is less chance of noise (or graininess, for you film types...), but a longer time for the shutter to be open is required. Shutter speed- This is how fast the shutter opens and closes, exposing the sensor to light. The speed is mostly expressed as a ratio to one second, like 1/15, 1/60, and all the way to 1/4000 or so on some cameras. The closer the number is to 1 second, the slower the shutter speed. As a rule of thumb, 1/60 of a second can be hand held without sign of shake. Add the VR, or IS, or whatever the lens calls it, and assume 1/15 of a second. A moving subject will NOT be caught at these slow speeds though. At a track, freeze a bike with 1/500 of a second, and pan with the bike at 1/30 would be a good starting point. You can set these using the (S) Priority mode. Set the shutter speed, and the camera sets the corresponding aperture. Aperture- Each lens has a variable aperture, or size of the opening through which light passes. The size of the opening is expressed by the f-stop, which is a ratio of the size of the opening to the distance down the lens barrel. The closer the number is to 1, the bigger the opening- and more light pours in. The depth of field is affected by the f-stop too. The closer the number is to 1, the less depth of field there is (think plane of focus in front of and behind where the camera is focused). The greater the number, the bigger the plane of focus. Three variables. That's it. Play with the S Priority mode, and the A Priority mode. Let the camera set the ISO. That's the best way to judge what your change of settings are doing, and everything is recorded in the metainformation- which you can get by running the cursor over the thumbnail and getting the properties. Learn by doing. On a side note, a woman came in today asking for help recovering some pictures. Used a Sandisk program called Rescue Pro. Some were deleted for a reason, I'm sure.... That was a HUGE dildo....