Exposure Compensation
Exposure compensation can be use when making photographs with difficult-to-meter content such as backlighting (like a portrait with the sun behind the subject) or a high amount of dark surfaces (like at a rock concert when only part of the stage is lit).
Assignment: Use your camera to shoot a series of photos where you compensate for the exposure, in 1 f-stop increments from -2EV to +2 EV, such as in the following examples: