The distance between the camera and the subject
The size of the iris which controls the amount of light entering the camera
A measurement of sensitivity to light
Decrease the ISO
Increase the shutter speed
Open the aperture
Make a picture look blurry
Freeze an image in time
Make a picture look like it is in slow motion
The light angle
How expensive the camera is.
How many exposures you can make.
How sensitive the camera is to light.
Auto-focus, ISO, and Flash.
ISO, Manual Focus, and White Balance.
Aperture, Shutter Speed, and ISO.
Here's an interesting quiz for you.