Aperture is one of the vital components used to construct creative and compelling photographs.  Often times, specific apertures can be used for certain situations or subjects.  Aperture is defined as the space in the lens that allows light to enter the camera and hit the sensor.  In order to alter the aperture you typically turn a dial or press a button on the camera body.  In turn, the hole letting in the light increases or decreases in size.  Consequently, more or less light will hit the camera’s sensor.