Parts of a Camera for Kidsby David Ferris
Since cameras first revolutionized image-making in the 19th century, they have endured as a tool of creative expression, a means of documentation, a source of news and myriad other functions. Cameras essentially function by focusing light through a lens onto film, which preserves the image captured by the camera.
The camera body is the "box" that holds the contents. It is generally rectangular and can be constructed from almost anything. The most important characteristic of the body is that it is opaque (meaning it doesn't let any light in). The interior must be pitch-black in order for the image to be preserved on film.
The lens is the "eye" of the camera, the part through which light enters. Photographers can regulate the amount of light that gets in. Lenses are equipped with focusing devices (often adjustable rings that can sharpen or blur according to desired effect) and aperture control, which determines how wide the "eye" opens.
The shutter control is like the eyelid: It moves the lens (the "eye") open and closed. Shutters can be adjusted to let in a lot of light or just a little, depending on the environment and the kind of picture the photographer wants to take. The "shutter release" refers to the part that triggers the shutter mechanism.
The viewfinder lets the photographer get a sense of the scene being photographed. The viewfinder has a separate lens and mirror. While they don't provide an exact image of the picture to be taken, it offers an approximation and is an important guide for picture-taking.