Your Lens
Much like a pair of glasses for your camera, the lens is made form a group of optical lens elements. The lens for your camera is the same as the ones used in a telescope and microscope. It is probably the most important part of your camera. The lens allows light to enter the camera body to the sensors.
Cameras today have what is called an iris to help adjust the amount of light that is allowed through the lens to the sensors. The sensors will adjust the focus of your camera (if on auto focus) to achieve the best picture possible. That is why many professional photographers will tell you to step closer to the subject as possible for the best results.
Using the auto zoom is great if you are not able to get close to the subject but the photos have a tendency to appear on the grainy side.
There are two different types of lens for a camera the interchangeable and the fixed. With the fixed lens you cannot remove it from your camera, and you are limited to the preset specifications of focal length set by the manufacture. With interchangeable lens you can go from a simple focal length to great lengths and capture some awesome shots. And within the two types of lens there are once again two types. There is the auto focus where you have no control over the focusing of the lens and the manual focus where you have total control over the focus of the lens. The DSLR camera’s have both features added to their lenses.
References:
Wikipedia.com
Orange flower
Olympus E-500, 14-45mm lens
