Definition: A camera body is a basic part of a digital model. In the body, you can find the LCD screen, the controlling buttons, the image sensor inside the camera and the attached circuitry.
Commonly, the body is roughly shaped as a rectangle. For basic cameras, the body includes a built-in lens which is in a fixed position (for example, with point and shoot models aimed at the beginning level). For a high-end camera body (with a digital SLR model, for example), you can use the lenses which can be interchangeable, or in another words, removed and replaced by other ones.