Even the best photographer in the world won't be able to get a good photograph if their camera shakes while taking the photo. Camera shake can often result in a blurry picture and it has ruined many a good shot. Single-lens reflex (SLR) cameras often vibrate or shake because the mirror jumps up when the shutter is pressed. You can lock the mirror up before pressing the shutter to avoid this on some models, but if you do, you can't see through the viewfinder.
There are various camera support items to help stabilize the camera and eliminate camera shake. The simplest form is to use a shutter release cable which lets you release the shutter from a remote spot without having to hold the camera. There are also items such as image stabilizers, which are sometimes built into cameras or lenses to stabilize the image. Clamps, monopods and tripods are also popular tools for keeping a camera steady.
To ensure absolutely sharp photographs, you must use some type of camera support. A good camera support should be strong and firm as well as compact and lightweight. It should let you adjust the height and angle of the camera as much as possible. It's impossible to use a support all of the time, but it's a good idea to use one when possible.
Supports can range in price from about $20 to several hundred.