Exposure refers to the amount of light that reaches the camera sensor when a photo is taken. An underexposed image appears too dark, lacking detail in shadows and midtones, while an overexposed image appears too bright, often losing detail in highlights. These effects can result from various factors such as lighting conditions and camera settings.

Adjusting exposure involves altering the overall brightness levels of an image to correct for underexposure or overexposure. By doing so, we aim to balance the distribution of light and dark tones, improving the visibility of details and achieving a more visually pleasing result.