How do I do night or low light photography?

Light painting is a photographic technique in which exposures are made using a handheld light source, usually at night or in a darkened room. The light can either be used to selectively illuminate parts of the subject or to "paint" a picture by shining it directly into the camera lens. Light painting requires a sufficently slow shutter speed, usually a second or more. Like night photography, it has grown in popularity since the advent of digital cameras because it allows photographers to see the results of their work immediately.