Pinhole spy cameras are defined as state of the art cameras that are so small that they can be hidden inside a picture frame, a stuffed animal, a lamp, or anything else. Most of them are as small as a quarter, and some even newer models are smaller. As one can imagine, the lens is not as big as the spy cam but offers a wide viewing range and is practically the only part of the spying instrument that cannot be hidden. Since the camera is so small and can be hidden, they are virtually impossible to detect.

Usually, all that is needed to operate such cameras is a VCR, and a pair of batteries or a 9V battery, depending on the model. Many pinhole spy cameras offer even more than just recording. For example, there are models that have built in smoke detectors, air purifiers, or motion sensors. New pinhole spy camera technology is evolving constantly. The models bought most often are the ones with built in motion sensors, as they start recording only when motion is detected, saving the user lots of time and videotape.

Pinhole spy cameras are often used for surveillance and for protection. Many employers use them to keep track of worker productivity and to keep employees from stealing supplies, and may concerned parents used them to keep an eye on their babysitter.

The signal from pinhole spy cameras can be transmitted to a live feed or it can be recorded for later viewing. These options, along with the relatively low price of the equipment, make pinhole spy cameras a good security investment.