What is exposure in a digital camera?

Exposure is the combination of shutter speed and aperture used to expose the image sensor in a digital camera.

When the image sensor receives the right amount of light, your picture comes out correctly exposed.

The camera's light meter determines how big to open the aperture (the hole to allow light in) and for how long (the shutter speed).

If the image sensor receives less light than it requires, your picture comes out under-exposed.

If the image sensor receives more light than it requires, your picture comes out over-exposed.